k*2^n-1 primes in 2008
 

Here is the list of 100 largest primes of form k*2^n-1, k>=3 discovered in 2008. Based on the Top-5000 list maintained by prof. Caldwell.

Ranking:
r1, rank among k*2^n-1, k>=3 found in 2008
r2, rank among all known primes

[CODE]
----------------------------------------------------------
r1 r2 description digits who date
----------------------------------------------------------
1 17 3*2^4235414-1 1274988 L606 Apr 2008
2 20 485767*2^3609357-1 1086531 L622 Jun 2008
3 22 3139*2^3321905-1 999997 L185 Jan 2008
4 24 113983*2^3201175-1 963655 L613 May 2008
5 26 5*2^3059698-1 921062 L503 Nov 2008
6 29 4348099*2^2976221-1 895939 L466 Dec 2008
7 40 5*2^2460482-1 740680 L503 Nov 2008
8 49 5077*2^2198565-1 661838 L251 Oct 2008
9 54 23*2^2141626-1 644696 L545 Apr 2008
10 57 1003*2^2076535-1 625103 L51 Dec 2008
11 58 9*2^2060941-1 620407 L503 Aug 2008
12 64 25*2^1977369-1 595249 L426 Oct 2008
13 70 15*2^1837873-1 553257 L632 Dec 2008
14 73 33*2^1813526-1 545928 L621 Oct 2008
15 77 5077*2^1753317-1 527805 L251 Apr 2008
16 80 19*2^1684813-1 507181 L503 Jun 2008
17 83 63*2^1659338-1 499513 L503 Jul 2008
18 84 61*2^1654383-1 498021 L503 Jul 2008
19 85 69*2^1649423-1 496528 L621 Aug 2008
20 103 19709699*2^1521540-1 458037 L421 Oct 2008
21 107 9*2^1481821-1 446074 L503 Apr 2008
22 113 21*2^1452771-1 437329 L503 Apr 2008
23 115 19*2^1434165-1 431728 L503 Apr 2008
24 116 113*2^1425998-1 429271 L257 Jun 2008
25 121 127*2^1398889-1 421110 L486 Feb 2008
26 122 1564347*2^1398269-1 420928 L466 Feb 2008
27 125 113*2^1389674-1 418336 L257 Sep 2008
28 142 81*2^1335675-1 402081 L268 Jun 2008
29 149 99*2^1292395-1 389052 L282 Apr 2008
30 159 2084259*2^1257787-1 378638 L466 Jan 2008
31 162 49*2^1257295-1 378486 L217 Apr 2008
32 165 27*2^1253870-1 377454 L65 Jun 2008
33 175 19581121*2^1229561-1 370143 p49 Jul 2008
34 184 5*2^1194164-1 359480 L478 Jan 2008
35 190 21*2^1170083-1 352232 L503 Mar 2008
36 192 27*2^1163629-1 350289 L503 Mar 2008
37 193 55*2^1162155-1 349846 L545 Mar 2008
38 199 31*2^1142093-1 343806 L503 Apr 2008
39 205 63*2^1126551-1 339128 L323 May 2008
40 209 33*2^1115902-1 335922 L488 Mar 2008
41 210 27*2^1108214-1 333608 L590 Mar 2008
42 221 55*2^1075711-1 323824 L545 Mar 2008
43 224 107*2^1070256-1 322182 L621 Aug 2008
44 226 133*2^1065655-1 320797 L632 Dec 2008
45 227 257*2^1064062-1 320317 L632 Dec 2008
46 228 217*2^1059961-1 319083 L639 Dec 2008
47 238 217*2^1026869-1 309121 L632 Dec 2008
48 239 91*2^1026521-1 309016 L323 Dec 2008
49 243 205*2^1019679-1 306957 L632 Nov 2008
50 248 729*2^1003373-1 302049 L466 Dec 2008
51 257 215*2^999170-1 300783 L323 Oct 2008
52 262 291*2^996371-1 299941 L261 Jun 2008
53 264 75*2^995721-1 299744 L257 Jan 2008
54 267 93*2^990684-1 298228 L282 Sep 2008
55 270 403*2^981831-1 295564 L284 Dec 2008
56 271 317*2^981378-1 295427 L623 Aug 2008
57 272 303*2^978724-1 294628 L548 Dec 2008
58 278 145*2^972835-1 292855 L639 Nov 2008
59 279 61*2^971585-1 292479 L80 Feb 2008
60 280 79*2^969795-1 291940 L80 Mar 2008
61 281 229*2^969073-1 291723 L268 Oct 2008
62 282 95*2^968636-1 291591 L80 Mar 2008
63 283 143*2^968622-1 291587 L621 Nov 2008
64 285 255*2^962590-1 289771 g320 May 2008
65 286 135*2^961897-1 289562 L323 May 2008
66 290 135*2^959059-1 288708 L616 May 2008
67 292 10474035*2^953628-1 287078 L18 Dec 2008
68 294 3234846615*2^949441-1 285820 p113 Apr 2008
69 297 167*2^945934-1 284757 L621 Oct 2008
70 301 21547*2^936473-1 281911 L284 Mar 2008
71 303 167*2^934492-1 281313 L621 Oct 2008
72 304 291*2^934097-1 281194 L261 Apr 2008
73 305 273*2^930663-1 280160 L260 Apr 2008
74 307 3313*2^928263-1 279439 L251 Dec 2008
75 308 397*2^926925-1 279035 L644 Dec 2008
76 310 209*2^921484-1 277397 L421 Sep 2008
77 315 263*2^916202-1 275807 L426 Jul 2008
78 316 285*2^915913-1 275720 L261 Mar 2008
79 317 259*2^914173-1 275196 L639 Oct 2008
80 318 331*2^913201-1 274904 L543 Oct 2008
81 319 10474035*2^910955-1 274232 L18 Dec 2008
82 320 83*2^910716-1 274155 L545 Mar 2008
83 321 399*2^906480-1 272881 L644 Dec 2008
84 325 93*2^903187-1 271889 L282 Jan 2008
85 329 6465*2^897008-1 270031 L20 Sep 2008
86 336 165*2^889902-1 267890 L268 Aug 2008
87 337 7195377*2^888888-1 267589 L284 Apr 2008
88 338 1545*2^887559-1 267186 L251 Dec 2008
89 340 167*2^885664-1 266614 L621 Aug 2008
90 343 285*2^881240-1 265283 L323 Jan 2008
91 344 759375*2^880769-1 265144 L284 May 2008
92 345 193*2^880287-1 264996 L323 Jan 2008
93 346 117*2^877874-1 264269 L488 Jan 2008
94 349 135*2^876997-1 264005 L260 Feb 2008
95 352 3539*2^869868-1 261860 L251 Jun 2008
96 353 157*2^869073-1 261620 L585 May 2008
97 359 10474035*2^860172-1 258945 L18 Nov 2008
98 360 203*2^859602-1 258769 L268 Oct 2008
99 364 24949*2^859435-1 258721 L468 Nov 2008
100 369 736320585*2^856778-1 257925 L426 Oct 2008
----------------------------------------------------------

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