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 A106131 #21 Oct 16 2022 03:22:54
%S A106131 1,2,3,4,8,10,57,59,69,6914,613376,613403,613431,613432,613436,613447,
%T A106131 613453,613483,613484,613507,613511,613513,613516,613531,613535,
%U A106131 613541,613547,613579,613580,613597,613607,6384425453,6384425504,6384425519,6384425555
%N A106131 Numbers k such that the k-th semiprime == 6 (mod k).
%C A106131 a(42) > 10^12. - _Lucas A. Brown_, Oct 19 2020
%H A106131 Lucas A. Brown, <a href="/A106131/b106131.txt">Table of n, a(n) for n = 1..41</a>
%H A106131 Lucas A. Brown, <a href="https://github.com/lucasaugustus/oeis/blob/main/semiprimemods.py">semiprimemods.py</a>
%e A106131 a(5) = 8 is a term because the 8th semiprime is 22 and 22 == 6 (mod 8).
%t A106131 Module[{sp=Select[Range[10^7],PrimeOmega[#]==2&]},Flatten[ Position[ Thread[ {sp, Range[ Length[sp]]}],_?(Mod[#[[1]],#[[2]]]==6&),{1}, Heads-> False]]] (* _Harvey P. Dale_, May 09 2015 *)
%Y A106131 Cf. A001358, A356135.
%K A106131 hard,nonn
%O A106131 1,2
%A A106131 _Shyam Sunder Gupta_, May 07 2005
%E A106131 a(1)-a(4) and a(32)-a(41) by _Lucas A. Brown_, Oct 19 2020