Smallest n such that 2*b^n-1 is prime

Wanted values[]

405, 6X8, 70E, 75E, 800, 835, 855, 8XE, E09, E52, E72

Remain at n=1000[]

8E, 122, 175, 192, 1E0, 1E2, 20X, 213, 278, 27X, 27E, 36E, 376, 39E, 3E8, 402, 405, 412, 436, 443, 45E, 472, 479, 4X2, 4X8, 4E8, 555, 5X5, 608, 662, 688, 689, 6X5, 6X8, 70E, 738, 74E, 752, 75E, 765, 800, 835, 83E, 852, 855, 856, 864, 8XE, 918, 91X, 92E, 942, 972, 982, 9E5, X3E, X72, X95, XXE, E09, E0E, E24, E28, E52, E5E, E72, E78, EE8, EEE

bases end with 0 remain at n=1000[]

1E0, 800

bases end with 1 remain at n=1000[]

(none)

bases end with 2 remain at n=1000[]

122, 192, 1E2, 402, 412, 472, 4X2, 662, 752, 852, 942, 972, 982, X72, E52, E72

bases end with 3 remain at n=1000[]

213, 443

bases end with 4 remain at n=1000[]

864, E24

bases end with 5 remain at n=1000[]

175, 405, 555, 5X5, 6X5, 765, 835, 855, 9E5, X95

bases end with 6 remain at n=1000[]

376, 436, 856

bases end with 7 remain at n=1000[]

(none)

bases end with 8 remain at n=1000[]

278, 3E8, 4X8, 4E8, 608, 688, 6X8, 738, 918, E28, E78, EE8

bases end with 9 remain at n=1000[]

479, 689, E09

bases end with X remain at n=1000[]

20X, 27X, 91X

bases end with E remain at n=1000[]

8E, 27E, 36E, 39E, 45E, 70E, 74E, 75E, 83E, 8XE, 92E, X3E, XXE, E0E, E5E, EEE

1 to 100[]

	+1	+2	+3	+4	+5	+6	+7	+8	+9	+X	+E	+10
0+		1	1	1	4	1	1	2	1	1	2	1
10+	2	4	1	1	2	2	1	X	1	1	6	1
20+	2	6	1	2	E4	1	1	6	6	1	6	1
30+	1	2	2	1	2	1	2	4	1	2	4	4
40+	1	2	1	1	38	1	1	2	1	3	2	5
50+	3	2	2	1	4	1	540	4	1	1	44	2X
60+	2	E0	1	1	12	7	1	2	2	1	8	1
70+	2	X	1	20	50	1	1	2	3	5	2	1
80+	1	2	1	1	36	2	4	58	6	1	1081X	2
90+	2	14	20	1	2	1	1	28	1	2	24	1
X0+	1	6	8	4	2	1	2	16	1	3	4	1
E0+	4	2	1	1	2	4	1	2	1	1	2	20

101 to 200[]

	+1	+2	+3	+4	+5	+6	+7	+8	+9	+X	+E	+10
100+	10	14	1	4	4	8	5	564	2	1	2	1
110+	1	2	1	2	170	X	70	2	2	1	8	7
120+	1	80390	2	2	4	1	1	6	1	2	2	1
130+	2	4	2	1	2	2	1	2	3	1	68X	1
140+	6	36	1	2	2	3	1	2	1	15	4	2
150+	1	2	39	6	6	1	1	10	3	2	754	1
160+	1	4	13	1	16	1	3	90	1	6	10	2
170+	1	12	1	1	4EX4	1	130	26	2	2	X	1
180+	3	2	4	1	2	1	4	2	2	1	2	1
190+	4	17XX	1	2	1X	24	2	X0	1	1	2	5
1X0+	2	2	48	13	18	2	1	6	2	1	4	1530
1E0+	2	214E0	1	2	10	1	6	2X8	1	1	36	2

201 to 300[]

	+1	+2	+3	+4	+5	+6	+7	+8	+9	+X	+E	+10
200+	1	18	2	4	2	1	2	30	1	2522	4	1
210+	1	6	1E2EX	1	2	E	1	6X6	1	1	2	2
220+	4	62	5	1	X	6	6	4	1	1	2	1
230+	9	10	1	68	2	1	1	2	12	3	2	3
240+	1	10	1	50	30	1	8	4	2X	1	376	3
250+	13	12	1	6	2	3	1	4	5	4	X	1
260+	6	4	2	1	2	3	1	8	3	1	8	1
270+	3	2	2	1	4	2	1	2236	1	1418	10164	2
280+	1	2	1	3	18	4	2	4	8E	1	290	E
290+	16	28	1	5	94	2	3	4	1	1	X	7
2X0+	2	2	1	1	6	1	1	2	5	333	2	1
2E0+	3	390	13	3	4	2	1	4	1	1	380	1

301 to 400[]

	+1	+2	+3	+4	+5	+6	+7	+8	+9	+X	+E	+10
300+	2	812	2	16	2	6	1	2	1	1	10	1
310+	3	4	2	2	126	4	8	2	6	1	2	1
320+	86	2	2	1	6	4	6	16	1	2	30	2
330+	1	2	1	2	470	1	2	22	1	3	6	100
340+	26	2	17	1	16	1	2	4	1	3	22	1
350+	3	6	3	1	14	2	1	18	2	39	5E8	6
360+	1	14	1	2	3X	1	1	2	20X	2	29X02	1
370+	1	6	2	1	8	30068	3	118	1	1	20	2
380+	3	24	1	1	2	3	1	5X0	X	8	2	19
390+	4	2	3	1	70	1	1	4	1	970	16X6	1
3X0+	7	2X	1	2	8	E	1	30	3	1	2	3
3E0+	1	4	2	3	50	2	2	2250	2	8	8	1

401 to 500[]

	+1	+2	+3	+4	+5	+6	+7	+8	+9	+X	+E	+10
400+	1	62E10	E	2	???	1	77	46	3	1	22	1E
410+	7	8E9X	1	66	4	1	2	16	1	6	6	3
420+	1	2	1X	4	138	2	1	2	1	2	X0	1
430+	12	220	1	1	2	4E96	1	2	1X	2	2	14
440+	1	8	41X0	E	136	1	3	6	122	2	36	2
450+	4	76	1	1	60	1	14X	8	1	1	105X0	70
460+	1	2	1	1	X	1	3	X	X	3	2	1
470+	1	9726	4	1	10	9	X	346	1743	7	2	6
480+	X	10	2	3	6	4	2	X	1	12	390	1
490+	3	4	1	3	2	2	1	8	2	18	X	2
4X0+	86	6199X	3	1	2	4	2	2EX96	1	2	252	2
4E0+	440	2	6	1	2	1	1	299X	1	2	70	1

501 to 600[]

	+1	+2	+3	+4	+5	+6	+7	+8	+9	+X	+E	+10
500+	2	X	340	1	86	1	1	1X	2	1	2	605
510+	3	762	2	1	254	8	2	4	1	1	2	1
520+	1	52	1	4	2	1	9	336	26E	130	52	1
530+	2	4	2	82	4	1	8	2	3	1	6	50
540+	5	1X	7	1	80	2	1	4	1	13	164	1
550+	5	4	3EX	1	571X	1	582	238	19	1	4	1
560+	7	6	2	3	2	7	1	11X	1	12	40	1
570+	1	80	1	6	38	1	1	X	6	1	2	2
580+	20	2	1	2	16	75	53	86	13	9	2	4
590+	1	12	39	1	8	1	1	236	8	10	2	2
5X0+	58	4	26	69	1X97X	4	1	2	1	1	2	9
5E0+	4	2	1	6	2	83	3	52	1	1	4	22

601 to 700[]

	+1	+2	+3	+4	+5	+6	+7	+8	+9	+X	+E	+10
600+	8	66	1	26	2	43	1	35E0	3	1	4	2
610+	1	6	5	1	E0	2	4	236	2	1E8	34	4
620+	1	2E8	3	1	2	1	1	2	5	6	2	5E
630+	1	4	X3	5	4	1	6	26	12	2	12	1
640+	23	306	3	1	156	2	4	6	223	246	2	1
650+	20	4	46	58	16	2	1	8	7	1	60	1
660+	1	1E486	1	1	2	56	34	2	1	15	46	2
670+	125	84	1	4	E0	1	3	16	1	2	2	9
680+	3	2	6	4	E4	1	1	101X	11E40	2	5X	5
690+	2	8	1	1	250	30	2	6	2	4	148	2
6X0+	4	1X	1	3	13670	1	3	???	2	1	1E6	4
6E0+	1	6	1	1	2	1	7	2	18	1	8	4

701 to 800[]

	+1	+2	+3	+4	+5	+6	+7	+8	+9	+X	+E	+10
700+	1	10	12	30	790	1	1	2	10	2	???	1
710+	6	4	26	3	2	18	1	2	3	3	EE6	1
720+	3	4	1	3	10	3	2	48	1	1	30	1
730+	1	2	2	E40	104	1	4	253X	2	18	3X	1
740+	1	4	4	6	522	21	2	2	1	1	31EE8	22
750+	1	7X3X	1	1	14	3	2	4	1	3	???	3
760+	1	2	3	2	124X	6	16	2	3	1	62	11
770+	2	X	47	2	4	2	5	190	3	1	2	1
780+	3	2	1	4	2	2	1	18	3	13	X	6
790+	E38	X	1	1	2	1	2	6	13	1	6	2
7X0+	710	6	2	5	2	1	1	6	1	2	1X	2
7E0+	1	6	30	1	2	7	1	20	1	10	6	???

801 to 900[]

	+1	+2	+3	+4	+5	+6	+7	+8	+9	+X	+E	+10
800+	3	2	1	1	14	2	6	4	7	2	2	9
810+	2	2	1	2	18	1	1	12	2	1	18	1
820+	4	184	1	18	44	5X0	4	396	169	1	12	6
830+	1	86	1	1	???	E2	1	8	1	2	EXE4	1
840+	53	1X	2	4	16	1	2	X22	1	4	25X	1
850+	3	4712	3	63	???	8X1E	1	6	1	2	5X4	1
860+	3	2	10	39E22	108	1	12	2	6	1	416	289
870+	1	26	1	4	4	332	2	61X	12	4	X	4
880+	18	2	X65	1	4	5	7X	10	6	X	EX	3
890+	1	X	387	3	60	1	5	8	3	1	2	1
8X0+	6	42	1	1	6	3E8	1	2	3	2	???	25
8E0+	2	4	2	2	132	1	6	2	10	E	4	1

901 to X00[]

	+1	+2	+3	+4	+5	+6	+7	+8	+9	+X	+E	+10
900+	1	6	E	46X	2	41	4	320	1	85	30	3
910+	1	22	1	11	38	10	4	365EX	1	11513	10	550
920+	6	4	3	1	4	2	2	4	1	1	1334	1
930+	2	2	X	1	6	2	1	8	6	1	4	1
940+	1	4264	1	260	40	1	20	2	20	1	126	1
950+	1	38	2	1	528	32	4	10	1	1	34	13
960+	16	70	1	2	2	71	1	2	1	20	500	5
970+	11	7852	93	1	2	2	11	4	1	26	14	5
980+	2	2442	1	1	210	XE6	1	2	1	1	56	10
990+	6	26	2	4	140	1	8	X	28	4	2	4
9X0+	1	2	1	4	2	1	3	2	3	1	6	2
9E0+	1	46	1	2	1E06	2	9	2	16	X6	2	1

X01 to E00[]

	+1	+2	+3	+4	+5	+6	+7	+8	+9	+X	+E	+10
X00+	3	190	2	1	2	69	6	530	1	2	4	1
X10+	3	14X	1	55	10	6	1	2	4	14	4	1
X20+	6	38	6	7	2	1	4	20	2	2	10X	3
X30+	1	2	1	6	16	1	2	8	1	1	19100	3
X40+	879	2	2	30	13X	2	2	4	4	2	X	1
X50+	1	2	24	9	4	1	54X	2	22	1	2	1
X60+	4	10	20	5	20X	13	1	2	1	11	62	7E
X70+	1	3862	9	7	2E0	3	1	4	92	1	20	3
X80+	180	14	4	1	6	1	2	32	1	6	10	2
X90+	3	12	15	31	1446	5	1	26	61	2	24	1
XX0+	1	2	X	22	2	4	6	13X	1	27	23X2	9
XE0+	X	2	2	5	2E0	3	2	X0X	2	1	6	1

E01 to 1000[]

	+1	+2	+3	+4	+5	+6	+7	+8	+9	+X	+E	+10
E00+	1	2	5	40	2	X4	1	2	???	1	856E8	1
E10+	2	4	2	5	4	1	4	2	1	6	2	7
E20+	1	2	1	2531	52	X56	1	1744	2	3	14	55
E30+	2	14	2	331	4	1	1	32	1	1	2	2
E40+	3	6	3	1	2	30	2X	760	2	268	4	2
E50+	2	???	46	2	2	1	1	224	2	1	3016	3
E60+	1	2	42	1	4	1	188	10	1	1	76	3
E70+	8	???	3	1	34	1	6	16290	2	20	4	1
E80+	1	X	2	6	16	1	1	14	3	2	82	11
E90+	7	4	1	1	10	128	X	2	4	2	146	1
EX0+	79	4	1	13	18	49	3	6	13	11	2	6
EE0+	1	936	8	1E	2	86	24	17X70	1	16	3080	3