%I A141232
%S A141232 2047,3277,4033,8321,65281,80581,85489,88357,104653,130561,220729,
%T A141232 253241,256999,280601,390937,458989,486737,514447,580337,818201,838861,
               877099,
%U A141232 916327,976873,1016801,1082401,1145257,1194649,1207361,1251949,1252697,
               1325843,1397419,1441091,1507963,1509709,1530787,1678541,1811573,2004403
%N A141232 Overpseudoprimes in base 2: A137576((a(n)-1)/2)=a(n).
%C A141232 Numbers are found by prime factorization of numbers from A001262 and 
               a simple testing of the conditions indicated in comment to A141216.
%C A141232 All composite Mersenne numbers (A001348), Fermat numbers (A000215) and 
               squares of Wieferich primes (A001220) are in this sequence. - Vladimir 
               Shevelev (shevelev(AT)bgu.ac.il), Jul 15 2008
%D A141232 Vladimir Shevelev, On an invariant of divisors of Mersenne numbers, preprint.
%D A141232 V. Shevelev, Process of "primoverization" of numbers of the form a^n-1, 
               http:// arxiv.org/abs/0807.2332
%Y A141232 Cf. A001262 A141216 A001567 A002326.
%Y A141232 Sequence in context: A145590 A038462 A001262 this_sequence A062568 A075954 
               A011561
%Y A141232 Adjacent sequences: A141229 A141230 A141231 this_sequence A141233 A141234 
               A141235
%K A141232 nonn
%O A141232 1,1
%A A141232 Vladimir Shevelev (shevelev(AT)bgu.ac.il), Jun 16 2008, Jun 20 2008, 
               Jul 31 2008