|
| |
|
|
A141232
|
|
Overpseudoprimes to base 2: a(n) = A137576((a(n)-1)/2).
|
|
24
| |
|
|
2047, 3277, 4033, 8321, 65281, 80581, 85489, 88357, 104653, 130561, 220729, 253241, 256999, 280601, 390937, 458989, 486737, 514447, 580337, 818201, 838861, 877099, 916327, 976873, 1016801, 1082401, 1145257, 1194649, 1207361, 1251949, 1252697, 1325843
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,1
|
|
|
COMMENTS
| Numbers are found by prime factorization of numbers from A001262 and a simple testing of the conditions indicated in comment to A141216.
All composite Mersenne numbers (A001348), Fermat numbers (A000215) and squares of Wieferich primes (A001220) are in this sequence. - Vladimir Shevelev, Jul 15 2008
C. Pomerance proved that this sequence is infinite (see Theorem 4 in the third reference). - Vladimir Shevelev, Oct 29 2011
|
|
|
LINKS
| V. Shevelev, Overpseudoprimes, Mersenne Numbers and Wieferich primes, arXiv:0806.3412
V. Shevelev, Process of "primoverization" of numbers of the form a^n-1, arXiv:0807.2332
V. Shevelev, On upper estimate for the overpseudoprime counting function, arXiv:0807.2332,v.8.
|
|
|
FORMULA
| sum{n:a(n)<=x}1<=x^(3/4)(1+o(1)).
|
|
|
CROSSREFS
| Cf. A001262, A141216, A001567, A002326.
Sequence in context: A145590 A038462 A001262 * A062568 A180065 A075954
Adjacent sequences: A141229 A141230 A141231 * A141233 A141234 A141235
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| Vladimir Shevelev (shevelev(AT)bgu.ac.il), Jun 16 2008
|
| |
|
|
