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 A297413 #17 Sep 06 2021 10:21:39 %S A297413 2,3,6,7,14,19,38,42,43,86,114,127,163,254,258,326,379,487,758,762, %T A297413 883,974,978,1459,1766,2274,2647,2918,2922,3079,3943,5294,5298,5419, %U A297413 6158,7886,8754,9199,10838,11827,14407,15882,16759,18398,18474,18523,23654,23658,24967,26407,28814,32514,33518,37046,37339,39367 %N A297413 Numbers k such that 2^m == 2 (mod m*(m-1)), where m=A019320(k). %C A297413 Also, numbers k such that A019320(k) belongs to A069051 or A217468. %o A297413 (PARI) is_A297413(k) = my(m=polcyclo(k,2)); Mod(2,m*(m-1))^m==2; %Y A297413 Cf. A069051, A217468, A297414. %Y A297413 Contains A297412 as a subsequence. %K A297413 nonn %O A297413 1,1 %A A297413 _Max Alekseyev_, Dec 29 2017