This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A195468 #39 Nov 09 2023 08:52:57
%S A195468 85487,104651,253241,280601,458987,580337,1082399,1207361,1251947,
%T A195468 1678541,2811269,3090089,5044031,5173601,5590619,9567671,10323767,
%U A195468 12263129,16324001,18073817,20647619,21303341,22849481,25080101,28527047,33627299,36307979,43363601,45414431
%N A195468 Lesser of overpseudo-twin-primes to base 2 defined in Comment.
%C A195468 If h_2(n) is the multiplicative order of 2 modulo n, r_2(n) is the number of cyclotomic cosets of 2 modulo n then, by the definition, n is an overpseudoprime to base 2 if h_2(n)*r_2(n)+1=n. These numbers are in A141232.
%C A195468 We call numbers {n,n+2} overpseudo-twin-primes to base 2 if each of them either prime or overpseudoprime to base 2, but no two are primes.
%H A195468 Amiram Eldar, <a href="/A195468/b195468.txt">Table of n, a(n) for n = 1..20863</a> (terms below 10^15)
%H A195468 Vladimir Shevelev, <a href="http://arxiv.org/abs/0806.3412">Overpseudoprimes, Mersenne Numbers and Wieferich primes</a> arXiv:0806.3412 [math.NT], 2008-2012.
%H A195468 Vladimir Shevelev, <a href="http://arxiv.org/abs/0807.2332">Process of "primoverization" of numbers of the form a^n-1</a>, arxiv:0807.2332 [math.NT], 2008.
%Y A195468 Cf. A141232, A002326, A006694, A137576, A001567, A002997, A194231, A192297.
%K A195468 nonn
%O A195468 1,1
%A A195468 _Vladimir Shevelev_, Oct 12 2011
%E A195468 More terms from _Amiram Eldar_, Sep 21 2019