FANDOM


These are the conjectured smallest Sierpinski/Riesel numbers for bases ≤1000, also the square bases ≤402 and the power-of-2 bases ≤210

Base 1E4 has the largest CK for all bases ≤1000, and it has been conjectured that base 1E4 has larger CK than ANY other base, and it is interesting to see if there were any CK > base 1E4's for bases >1000. Didn't take much searching, base 1254 has a much larger CK than base 1E4, S1254 has CK=X93X0883679XE07, and R1254 has CK=54X8E4X3X13E1042

The smallest CK for all bases ≤1000 is 4, and the smallest odd CK for all bases ≤1000 is 11, and it has been conjectured that 2 and 3 can never be Sierpinski/Riesel number to any base, but this conjecture is not true, 2 is Sierpinski number base 110X9695X887X2X75 (and now it is conjectured that this is the smallest base such that 2 is Sierpinski number), however, 3 can never be Sierpinski number, and 2 and 3 can never be Riesel number, in general, numbers of the form 2^r−1 can never be Sierpinski number, and numbers of the form 2^r+1 can never be Riesel number.

kconjectured smallest base such that k is Sierpinski numberconjectured smallest base such that k is Riesel number
1(none)(none)
2110X9695X887X2X75(none)
3(none)(none)
41212
53XEE2278(none)
62X2X
7(none)1938686132
81818
986X40(none)
X2828
E1212
10EXEX

Note that 2, 5, and 9 are not Sierpinski numbers for small bases, and 7 is not Riesel number for small bases (1, 3, and 7 are not Sierpinski numbers for any base, and 1, 2, 3, 5, and 9 are not Riesel numbers for any base), besides, all small bases with E is Sierpinski or Riesel number are == 12 mod 13, and in these bases 4 is also Sierpinski or Riesel number, thus E cannot be the CK for small bases.

Bases 2 to 100 Edit

baseconjectured smallest Sierpinski numberconjectured smallest Riesel number
239565206817
32029E39E01X1028027E722
4327591E143
578702148842
684X5841013
715E77XXX7X70670E5X1X7X2
83E12
9143462
X53875X80
EX425EX
10375274
11E0212
1244
13X292X0769529040E498E248436
1432759177X5
151E272
16292186
1730X9864600X2
1888
196E63X8
1X3X5X26E9
1E132338
20158X316868
21107EX6148842
22165105
2338X570
2427765306
2544
266032X28
272168X4065E66
28XX
2910X6538
2X66
2EX3X2X11X704
30111257410
31161045E8
321211
3380186552872
3433X3511173959
3588
3678X48915
371380480
3844
3926E4211084
3X88144895
3E812
408571X4X
4118541492
421414
43189E9122X8381X
4414716418EE
45117X3154
461919
4726803E70
481818
49830100
4X20E1351278
4E44
509991EX92
5189407978
5288
53106E76105286734X
544312
55XX
56717X8E72X189730
57X74619X0
581X1X
5966
5X64E136X8
5E119199X7X2277156EX8
6050E205
61X042X0
6244
6324462446
6437X0
651212
668E8634414E
678X84847X9890
68727191
69361862
6XE40310E06
6E88
701414
7197EX0X4XE1575740
722424
731XXE64
7424515746
7544
762323
7743X16E0682
782828
791214X430
7X3333
7E1EE221552
801503E51X697
81931013302
82XX
83490100
841519526
85149X
86205E43
877E96806
8844
898914082892
8X1EX6166653E3
8EX2492
90132527912
912X100
923232
93121046E56
94203X2283
957X18
962020
972499639846
982112
9913203880
9X5942
9E44
X0X566641547971584
X12601XX6
X23412
X312X210X
X44X15E57X12EX9X9
X588
X630E838E15399
X722211X8E5616247871726
X83838
X91212
XX41320199X1E5
XEXX
E01118
E111602170
E244
E37881974
E44459944599
E51X1X
E617391066
E766
E83X3X
E9375283E0229857932
EX1010
EE44E8862
1004E4E

Bases 101 to 200 Edit

baseconjectured smallest Sierpinski numberconjectured smallest Riesel number
101189156104XE8
10288
103X4763X330
10427073026
10544
1062449624496
1074027014X602
1081414
1092X2X
10X51160
10E1212
11036982X05744XE8E77E1
1119402082
1124444
11330370
1141X133
115102819XX
11637011X77
1172514270
11844
119187X45X
11X6969761E22
11E88
120542428E4
12114136
1221818
123XX5X55332
12490892
1252424
12666
12714E23740079311E20
1284X4X
12921401X4
12XE0173
12E44
13069005326X1386
1319X210
1321E52
133724154
1343030
1352828
1365757
1375662058
13888
1394848
13X1078833262925
13E212198
14046878061
14184463X916
14244
14380E060021430X5594
144XE7EX68X9X4E
145XX
14624612152
14777X077X0
1483E58
149166601X128E492
14X4949
14E1412
1506969
1516807629E6080
1521X1X
15355561X3X4
15410948
15544
1564161774722X26478
157E8662E16
1585X5X
15924EX386
15X12338
15EE6448X7X
1607878
16110X62868
1626262
1632X2X
16487230
1653232
1661693X743296
1672955X277X8
16844
16957E3X812X8
16X6276307783E
16E1818
1707E69812
1712020
17288
17310183073880
174197034202209
1751212
1763X3X
177910X3142
1786868
1794242
17X1X6876919919E9
17E44
1806E0777EX4X90
1812681249266
182812
1831E23X6X74
18466
1853434
1866565
187353941X7628
1886X6X
1895888300
18X1X1095128X975
18E88
1903939
1911258X1128
19244
193538669X792
1948595EE8
1953838
1963030
19710012
1982424
1992E62470445X606
19X540E0139E3
19EXX
1X04646
1X118618
1X27474
1X3549260591106
1X449XX940
1X544
1X62EXE810669
1X74853EX3614X60378
1X888
1X923724252
1XX1919
1XE1X1X
1E026043562X3XE
1E1E3E64128
1E2812
1E366
1E4924XE44391X5649731795912E69
1E53X234
1E66307E0XE
1E75190XX6222
1E844
1E91010
1EX26X6E
1EE41728318
2001694431

Bases 201 to 300 Edit

baseconjectured smallest Sierpinski numberconjectured smallest Riesel number
20115072
2028282
2031729495E6
2041E461180X2
20588
2069E9E
207170646280658
208XX
2096541X63338
20X13398
20E44
2107171
2114326X6477008
2121411
2138515X414X0
214X12E6
2151414
216189E691X8X7
2172X8
2188888
2197X7X
21X10E3X01566X5
21EEX12
22036E61184421
221545004EE6
22244
223E4X630
22411X48011X480
2254412
226100100
227490X72
2288X8X
2291X1X
22X1616
22E13X446408
2301212
23123884X7X31979442
2329292
23310984X0
2344040
23544
23656X38975650866
2371163761X8012
2383232
239392X35X
23X5656
23E88
240452X830576
241386276
2429462
2431414
24421928
2451818
2463X0445
2471154E78
24844
2499E6132X8301936068
24X754E41X86266E
24E2424
25013423X854
25166
2521212
25356EX014050
254475X14X2
255144X
256E9E9
2571179622892
25888
2591X0304242012
25X92518E692E3XEE
25E44
2604442232
2616871445172
262XX
2635454
26420362
26521452
26639X271279
2672006438
2683434
2693030
26X114383
26E2828
27057432711
271X062
27244
2732622084344090
27442X100
27588
2763890X65
27718648
278X8X8
279X87X81724
27X67977910
27E712154
28066
281113255411X4296
2827138
283105X82
284442899XX3E
28544
286E5E5
2879E71X739606
288XX62
28929E0066X6
28X113113
28EXX
290305920148
291612X83746
29288
2935X59046923759957E8
29442254566884X66
2955858
2967878
2976730123X0
29844
299102102
29X136415
29E1414
2X030E230E0
2X1X4386
2X2E4E4
2X32291X2XX52
2X4E059
2X51X1X
2X67070
2X7722518710767432856
2X8E8E8
2X94848
2XX4X3X6959
2XE44
2E092448E22395X1
2E12717X36748
2E23X3X
2E35742X80
2E41459
2E55X5X
2E65252
2E71E6304X844086
2E8XX
2E93838
2EX10E7922168
2EEE7X28X98
3002309193558

Bases 301 to 400 Edit

baseconjectured smallest Sierpinski numberconjectured smallest Riesel number
30124678
30244
303872X564XX6197286E82
304154459
305812
3061635132X
3072X100
30888
3099X9X
30X193402733E
30E13424
31012E12E
311880X210E6
31210462
313150104
3146867364170
31544
316X2X2
3174821043X36
3181084E
3191766618168790X
31X66
31E1818
3204E7625721679440
321411EX300830
3221414
3232020
32419X632866E
32588
3262379X2XE906E0
327830478
32844
329392082X0E6X
32X3910104E6
32E812
33014X14X
3313X370
332112112
3332782526
3347373
335812
3363333
33720042
3384444
3393928881E2
33X21285115X338
33E44
3403232
3413XE36E088390E2
34288
3432815E4
3448080
3451E284034
34612689961682E
3473E041380
348118118
34966
34X890323983
34E3434
3507272
351230122
35244
35329487X57966
354E9452
355146X
356475347896
35712901442
35811X11X
3591E25EX
35X51404168
35E88
360149149
3611544E6
3622112
3637E26X04
36424EX604E1375
36544
366162162
36752738819419046X9221724176
3681612
36922630X8376
36X2X388
36E3838
370EXEX
3713030
372124124
3731212
3746EX7X0
3752424
37616X845805
3776360E0
37844
3792X87X862974478
37X271630
37EXX
380983E
38169046
3824X4X
3831818
384343E9
3857474
3868X8X
3871684X00300070
38812X12X
3898633X55X24
38X238
38E44
390447963327062
39151375005258962
39228132
39338EX1544
39454163
39588
3961313X8543E1984X
39767EX56630X78
3981411
3992X2X
39X97476
39E1X1X
3X06666
3X1115616526
3X244
3X3168E029822
3X4115896X8869843
3X51428
3X6197197
3X766
3X8XX
3X921341X22002034
3XX1013E
3XE103X
3E09696
3E14XX0EE06
3E288
3E36501336
3E411600E243
3E544
3E6EE3E344234326
3E71010
3E813X13X
3E9150150
3EX2020
3EE6705X38XX8
400158X3X372

Bases 401 to 500 Edit

baseconjectured smallest Sierpinski numberconjectured smallest Riesel number
40147416
40258EX
40372150
4042X611E
4058282
4064646
40718961792
40844
40947E90884943136
40X7154E061E8X486
40E88
4107X7X
4112X66E8
412144144
413949615X04
414118899E50
415XX
41666
417126320120E02
418148148
4191098
41XX8E421380
41E44
42077E6X44E584
421160582
4225858
42311786678
4241919
4258484
426251X437258
4271830XX25X28
42888
429134134
42XEX529
42E149X
4307X01251025
431X80180E0
43244
4332X2X
434268591169E
43536X88
436238E1559
4377X160
4381X1X
439E408923XX
43X7676
43E1212
4402X468323590E
441X10413398
442XX
443719662912
444754136
44544
44680620978213908
44729164X042202698
448812
449359X6E8
44XX6X6
44E4444
4502323
451100100
4525X5X
453E6812X0
4546X995EX5
4558X20X
45663E01X3X
4571X210
45844
4591616
45X265E915722
45EX4494
460208179
46110012
46288
463163011217E5420
464X0206124E7E3
4659292
466199199
46740161XX6
46810162
469401X
46XE9X410E73
46E44
47036X13136807
4711717EE7E78443481XE184272
4721212
473598X878
47466
4753232
47617362X
4771320X596
478812
4795656
47X183183
47E88
4801E461EE94
48129179X660382
48244
48312204419X74
484589105
4859494
486143143
48714136
48816X16X
4892828
48X3E531E86E
48E1818
490723X
491268E30210288
492172172
49347302866
4948989
49544
496E067737912100680
49731E82801538222
49888
49939948776
49X7871E3
49E2424
4X0200200
4X183442760
4X2174174
4X366
4X41045860197053979
4X57812
4X66363
4X738X26E2
4X844
4X9349E550769042
4XX299212
4XE4X12
4E0144E51E969
4E115X650
4E26868
4E3248302764
4E4380135
4E588
4E61010
4E7725299X331E782
4E817X17X
4E987E92157XX
4EX183713
4EE44
5008888

Bases 501 to 600 Edit

baseconjectured smallest Sierpinski numberconjectured smallest Riesel number
50111X256413E3366
5028182
50314427530
5041504E
505XX
50637X9348432E477
50754186
5083X009XX312X
5096262
50X123123
50E5252
5103E104X2710
511834X2406
51244
5138518X1226782
514E1606
5153434
516747E7E4X
5173030
5181212
519114114
51X1576610576
51E2828
52020E20E
52114191416422
5226X2X
52328X0
5248X5E3
52544
526X1E8E139E5
5271E8E441702
5281485
529100100
52X211740
52E88
5301X87513916353E22
5312350014016
532XX
5334848
534321921297716X19
535X8X8
5361868
5377379X387902
53844
539XX244885E83X
53X1776E6
53E68124
5402805E2805E
54166
542194194
543108XX240702
54411507137X6
5453838
5465151
54735725083900
54888
54980983627X46XE4
54X1544X0
54E44
5501831E9
551380192
5522424
55330212
554110110
555XXXX
556X16XX19649
557454413998
5583412
559178178
55X169169
55EXX
560265806
56116080407457X0
56244
5633972340X
56439XXEE379138358
56588
566137243
56726145E3X3394265583948940
5687474
569130E72481163483X
56XX92X0
56E1458
57066
5714E678
5721X41X4
57326E0416EE4
574120672X216
57544
5761544818797
5773X0198
5781411
579136136
57X463118
57E1414
580247247
58183612620X59E2
58288
583X4X4
584156E616X1X3
585E467X
586114E91765X9
587537X4946
58844
589128128
58X39X795516321578542715
58E812
59010100
5917070
5921E21E2
59341844X6XEEE8
5945942
595E8E8
59611X11X
59733648
5982828
5997201266
59X59966488480
59E44
5X0530440E68
5X110XE411E36
5X2581E4
5X31459X5010
5X44312
5X53X3X
5X6372X
5X773246555926
5X81E81E8
5X91414
5XX269269
5XE5X5X
5E0182X64E29
5E115052
5E244
5E3X858785X46349EX0426151X0
5E41XX015292E
5E5XX
5E61846X11E05
5E733638
5E888
5E93326E4137028
5EX3XE113355
5EE812
600126126

Bases 601 to 700 Edit

baseconjectured smallest Sierpinski numberconjectured smallest Riesel number
6015216XE67103038
602142E
6037878
6046666
60544
6065656
607106649638
6088282
609154154
60X66
60E6262
610725183E415406700
611131X25392
6121E204
6132X2X
6141276X24240
61588
61630951299X
617230230
61844
619244862422870
61X28X0126709469
61E3232
6201159
6214401X2
622XX
62322XE6EX022793692
624137139
62528104
62625E1E8
62739EE74744E2
6281X12
6294502E210
62X2626
62E44
6301044
6311010
63288
633242123X2
634261896
6359X108
6364602420349727X99
6375515E41433E62
6388425
63966
63X686XE431480168X0E0208119
63E15418
640237237
641X262145600E6
64244
643151937813E599X
644E0E0
6451414
646124386XE6
6472020
6488787
6492078936982209865XE5X
64X1E923
64E88
6503030
6511799174X12EX1880
65215188
6531469434X6
6541416716996
65544
6561818
65719E8X2360
65821X21X
65911529041697E4
65X1419
65E1212
6604X0304X030
66114X7E0
66222220E
6633X3X
664327119455
665112112
666152152
6679070XX86
66844
669282282
66X2075167XE8445020E7973
66E6868
67032164
67118648
672224224
6734242
6743227316E
675441X2
676279279
6773E391X543XE0
678XX
679E4469EX
67X2X4126
67E44
6803244115010XEE55155494
6816E432
6828X8X
683796658X7599980
684543142
68588
6862196337921762535X6
6871002X0
6881414
6898080
68X188E20197066
68E873820X2
6901E31E3
691543010822
69244
693161284117268
6941607819753EE
695114118
696129129
69766
6989292
699989E51064X19922075776
69X1XE342X16
69E3412
6X0144144
6X163072
6X288
6X3122122
6X4E7X210
6X544
6X6345215692E37
6X7306666X6
6X8238124
6X9308
6XX293293
6XE6X6X
6E03469266E4
6E118X404X906
6E23232
6E31X5619EX
6E41010
6E511X814
6E6874179
6E72914290
6E844
6E92772XE9914
6EX383X82
6EE88
700431E276260X37

Bases 701 to 800 Edit

baseconjectured smallest Sierpinski numberconjectured smallest Riesel number
701214916
702242242
703154154
7049467397653
7051212
70666
707406661X384X398
7089494
709X46630
70X3899754498
70E44
7102806E96927849868
7111386162
7128X
713266012336E6
7146969
7151818
716111111
71740E2010418
71888
7198888
71X3772927756
71E21238
7202X632X63
721EX136
72244
7233030
7242E6X1E
725124124
726967E23E
72710012
72824X24X
729150688501193E864
72X30368
72E2424
7301919
73122E666740X8
732252252
7332X058581X4
73460X37079
73544
736102E4X57X84
737728183X247124X8
7381212
73910X10X
73X2E1X30
73EXX
74042331X
74114161702
742811
7434646
74416391961639196
7454X4X
7467238X41616
74718618
74844
7493434
74X81182
74E1474
75023X0X391E0
7518X820
75288
753E622X86
7545791112
75512X12X
7563838
7572E6E36
7588787
7592X2X
75X593188
75E44
7607979
76144075003E04256
7621818
76355X618666
76466
765132132
7661115542411E2
7672E6380
768XX
769232232
76X1846712X06
76E88
770E4752645
7711116X07X10892858
77244
773990411496
774430E918318E48348
7755212
7761791EX
7772X100
778268268
77932X04
77X671319853
77E1X1X
7801212
7816666
782346E
78323349961X43788
78463XX101E
78544
7868484
787277410768
78888
7898086E74
78X623168
78E2828
79039X8XE3EX01
791210210
7921485
79366
7944X823
795XX
796465210872
797310X10242
79844
7993050131430501314
79X1X3E
79E3X24
7X05E3E016227E
7X19696
7X21212
7X349309EXE171352
7X4370370
7X588
7X616X16X
7X710246762330X18
7X86E278
7X91E95X244275X
7XXE3E3
7XE44
7E0116116
7E13081X3389X8
7E2X8X8
7E31010
7E4323323
7E513X13X
7E626EX66
7E7150150
7E8154E
7E92020
7EX16E19778E13959E516515
7EE1E46X48E82
80020822082

Bases 801 to 900 Edit

baseconjectured smallest Sierpinski numberconjectured smallest Riesel number
8012E42616292
80244
803168XX33636X
8041E5976
80528142
80639X39X
80715072
8083838
8095242X6
80X182371E680
80E8282
810176176
8114646
81210100
8131X9X1X9X
81459623E
81544
8162X497X045172E277
817574943405X659E28
8181414
819185X652
81X3X139
81E88
820228228
8217X7E8
8223E12
823128128
824361903204623
82514496X
8262323
8271E12X10080
82844
82926013814X5X0
82X567701463X6
82EXX
83049100
83166
832292292
8332403697142
834503576876
835148148
83633E33E
8374E698
83888
839103E1E21320X8X
83X163163
83E44
840728548782587
8417757XE7576
842158294
843E0160
844341E86
8455858
846258XX3
8476604X16E68
8481212
8492X2X
84X126126
84E84914
8501381632069X
851128940X933X86
85244
8532E48X1266X6
85418E7805046E6030
85588
856114114
8571342E6
858XX
859EXEX
85X544X41598XE
85E1414
86066
861X3X2X303X0
8622X22X2
863302X5X44
8642E0E9599
86544
866931718671
867X0X0
868E454
86916371425778
86X3312
86E8888
87076X902748X22E245
8716110134X2
87288
8737X7X
874164X19
8751X1X
8762441E
87724109E8
87844
8797676
87X9X4125
87E1212
880XE67112557
8813978646XX16
882E8E8
883EX16108492
88430212
8858X
88675359
8872E243E8009349450E8
8882XX2XX
889136136
88X1098946X3E6
88E44
890285285
8913928260438836362
8921461
8932145XE698
8941919
895158114
896263263
8973060X25652
8983X3X
899X6X6
89X187X66
89E4444
8X01X31X3
8X154186
8X244
8X3100352
8X4176X011275E
8X55X5X
8X64EE52256656
8X7490230
8X888
8X99601X049XE948
8XX1E024212E3
8XE8X1X
8E023194
8E18686386872
8E2XX
8E31X1X
8E425X093890
8E544
8E633940470889
8E71616
8E83E12
8E9XX3818714
8EX66
8EE182408
90013309X4

Bases 901 to X00 Edit

baseconjectured smallest Sierpinski numberconjectured smallest Riesel number
9016E6208
902302302
9031212
904410919XE5390
90588
9064938333265
907964022X72
90844
9092E188155E2
90X100641X3687632
90E9292
9102X16
91128XEX0
9121X18
9133471XX9E9E0
914573362
9151462
9161X01X0
9174040
918308308
919E9X418268
91X1XX972632
91E44
920702E260E9305731
92170656E8478
92288
923302541054X
9244646
9251212
92655338113E94
92724X5011380
92830X267
92966
92X18599832371588
92E3232
930160160
9313041036
93244
9331027262X1566676
93413XX73
935168168
936153153
9375656
938104104
9392E82E8
93X591076
93E88
94038E38E
9412EE539298E461476884EE0
942314175
9432E14E84
9445503E5
94544
946404404
94735135204053822
948XX
949X73E61EX94
94X3911120
94E9494
950382177
951186270
952108108
9531414
954E699036E55
9551147X
956125276
957EX28
95844
9594141242X1266E46X
95X13771442342E16161128
95E1818
960X668073
961E430
96225438
96333000X03538E8
9641X6X6661126E960E
9651412
9661919
9679X665EE6
968142E
969408408
96X289289
96E44
97021XX7426X9X7
97137279X39376
9722242XX
97321282854
9741E01E0
97588
976368368
977110545X28X8136
978328272
9792X82X8
97X386386
97E2424
9802752E6
981200200
98244
983468766
984363363
985174174
986277E32X5
98766
98832X223
98916853021685302
98X2671036
98E1212
99028X3X9
9914441216
99288
99382352
99451E7737270
99544
9967070
997102X48E47E91326
998812
999212212
99X7X31E8
99E4X4X
9X0401013
9X127194X1017X6
9X2XX
9X315X15X
9X44949
9X56868
9X6194E39X71
9X72930101E6498
9X844
9X9380380
9XX1213604166E
9XE88
9E0729EX114523
9E11010
9E24444
9E31579E42633224
9E4260829
9E5103X
9E666
9E724697E549709578
9E833X33X
9E9134909498
9EX15016171X0
9EE44
X0019E19E

Bases X01 to E00 Edit

baseconjectured smallest Sierpinski numberconjectured smallest Riesel number
X0193688
X021212
X0312562146558
X041459
X05182182
X06670003503E2
X0716X936886652
X0888
X097272
X0X196X65362EE203140
X0EXX
X1016919696XX
X111855620998
X1244
X135454
X14137E50
X156267832X9E8
X16797797
X1757062
X18348348
X193X83X8
X1X2X18
X1E5252
X20206206
X21132E562E7128
X22231118
X234050885X
X24560485
X2544
X2658X1E1512943X93
X2713E77063XE2962
X2832E34X
X29424424
X2X2X69E
X2E3434
X302E11122
X3132E405686
X321414
X333030
X34E0X76EX83516E2
X351812
X3653102984E38E93
X37114258
X3844
X3940EE8514768
X3X39354308X0
X3E2812
X4015030E219
X41730312
X4288
X4384E94E7846
X443809443X0
X456X4X
X461212
X47X0X0
X48358358
X498X8X
X4XE8XX3738
X4E44
X502303X0
X5127E4X246430028518
X5211X98
X535662058
X5466
X5518X18X
X561234399
X57100100
X58X4235
X5974031X
X5X124428491123708X88
X5E88
X60E3E3
X611510449X0
X6244
X6333X84334X3X76X6681094
X6454X13E3
X65XX
X667878
X67186E2
X681212
X691546X0552872
X6XX50X240624295435
X6E58X8
X70X1X1
X7123410X6
X72341X4
X732X71X282094
X7449X136
X7544
X769X352479552
X777EE8032418
X7888
X79384384
X7X216216
X7E378E91XX864909872
X80451451
X81136XX52132
X821818
X8366
X84X2958
X85194105X
X864XX527EE
X87503X1310
X8844
X893001EX4405112
X8X2323
X8E3838
X90546555532
X917X150
X92XX
X93159662600
X9422E6727556
X9588
X96439439
X9710530424E430
X98124124
X991221EX
X9X1164X653563
X9E44
XX01X1313
XX13541236
XX2144374
XX3192380
XX4883222
XX52424
XX6132E700132271EX0
XX778X668
XX81411
XX9110110
XXX777X1333E
XXEXXXX
XE01010
XE154E4880012250568
XE244
XE31E7766021X97XE54
XE41081188
XE51419X
XE617232XE71
XE7716178
XE81414
XE93E212E0
XEXE76743723
XEEXX
E00224224

Bases E01 to 1000 Edit

baseconjectured smallest Sierpinski numberconjectured smallest Riesel number
E018062E8
E021X1X
E03147796277928
E04E0488
E0544
E06756371
E073578209E08
E084X4X
E091X3074402X0X
E0X1919
E0E88
E1019832804X210X42
E112E41112
E121212
E13XX83921079346
E1414907E7X85
E157474
E16E059
E174E214E2892
E1844
E19264264
E1X76020272491230
E1E812
E2047X4846X
E2166
E2212X12X
E2378EX0
E2432330230X0
E251321X4
E261414
E2730X6X99938
E2888
E29172402410
E2X88295X321273
E2E44
E30147988X1E49
E3117E7E0166002
E3258105
E33102102
E344312
E3594X1X8
E36182E53134215
E37136136
E381485
E39X22118
E3X17410E3
E3E149X
E405X5X
E4116186
E4244
E434694X4E700
E4420E191668E
E4588
E46417417
E47X44X0
E48398398
E4933E833X10
E4X63051E
E4E812
E5066
E5131X0X4579E8
E52X152
E535X7611X1EX
E54551202
E5544
E56450450
E576E61652
E581818
E59911419652
E5X444E8E
E5E1X1X
E6019X8X931492E
E61377X62537X2
E6288
E637070
E64419318
E651141E2
E66153X5498X
E6727993624028
E6844
E694242
E6X306664X7X3057467E5
E6EE8E8
E7064X93479
E7111X1090
E723X472
E7348262
E74E08
E7510X28
E765656
E77959X24198
E782112
E79295E9X504E0
E7X570570
E7E44
E80706X14936
E811605E24752X50
E82XX
E8328983X76
E84240240
E851E41E4
E86502502
E87657X1XX00
E883XX3XX
E891212
E8X806385
E8E3X234
E901391103138E2
E912XX0
E9244
E93451694880292
E943139919E239
E951341E8
E963948X
E9714100
E9888
E99342342
E9X199199
E9E5X258
EX01919
EX165X54X4E93602
EX23E43E4
EX35252
EX4258071E1E8
EX544
EX69999
EX721E404X782
EX832311
EX932132X
EXX66
EXEXX
EE014E14E
EE12E89E6133E78
EE213X13X
EE33838
EE49836973618X025916
EE588
EE65996E2XX94E
EE738XX19848
EE844
EE91932561662XX
EEX3341333
EEE2141084
10001818

Extra square bases up to 402 and extra power-of-2 bases up to 210 Edit

baseconjectured smallest Sierpinski numberconjectured smallest Riesel number
1030 = 362256256
10X1 = 372304X8
1154 = 382419419
1209 = 392394124
1228 = 2E23X25
1284 = 3X2203270
1341 = 3E21412
1400 = 402649649
2454 = 2108463068
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