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 A125773 #10 Jun 19 2022 02:21:36
%S A125773 35,297,1093,2186,2590,3279,3511,4372,5465,6558,7022,7651,8744,9837,
%T A125773 10533,10930,13116,14044,14209,21066,23175,24012,24577,26592,28088,
%U A125773 31599,35110,38621,42132,49154,987704,3020871,3074592,18368834,22655923,105713883,111503202,1084277175
%N A125773 Numbers k that are not powers of 2 such that 2^k mod k = 2^k mod k^2; or A068535 with powers of 2 excluded.
%C A125773 A068535 includes all powers of 2. a(3) = 1093 and a(7) = 3511 are the only known primes in this sequence. They belong to A001220 = Wieferich primes p: p^2 divides 2^(p-1) - 1. Note that most listed terms of this sequence are the multiples of Wieferich primes 1093 and 3511. No more terms in this sequence up to 6*10^6.
%t A125773 Do[f=PowerMod[2,n,n];g=PowerMod[2,n,n^2];If[f==g&&!IntegerQ[Log[2,n]],Print[n]],{n,1,6000000}]
%Y A125773 Cf. A068535 (Numbers k such that 2^k mod k = 2^k mod k^2).
%Y A125773 Cf. A001220 (Wieferich primes p: p^2 divides 2^(p-1) - 1).
%Y A125773 Cf. A125774 (Numbers k such that 3^k mod k = 3^k mod k^2).
%Y A125773 Cf. A125775 (Numbers k such that 5^k mod k = 5^k mod k^2).
%K A125773 nonn
%O A125773 1,1
%A A125773 _Alexander Adamchuk_, Dec 07 2006
%E A125773 More terms from _Amiram Eldar_, Jun 19 2022