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 A106129 #32 Oct 29 2022 04:42:43 %S A106129 1,2,5,37,38,58,61,70,77,613379,613413,613415,613429,613485,613509, %T A106129 613518,613521,613533,613543,613599,6384425449,6384425459,6384425463, %U A106129 6384425517,6384425557,6384425574,6384425634 %N A106129 Numbers k such that the k-th semiprime == 4 (mod k). %C A106129 a(28) > 10^12. - _Lucas A. Brown_, Oct 18 2020 %C A106129 a(28) <= 121769718289846, a(29) <= 121769718289883 and a(38) <= 121769718292241. - _Martin Ehrenstein_, Oct 28 2022 %H A106129 Lucas A. Brown, <a href="https://github.com/lucasaugustus/oeis/blob/main/semiprimemods.py">semiprimemods.py</a> %e A106129 a(3) = 5 is a term because the 5th semiprime is 14 and 14 == 4 (mod 5). %Y A106129 Cf. A001358, A357808. %K A106129 hard,more,nonn %O A106129 1,2 %A A106129 _Shyam Sunder Gupta_, May 07 2005 %E A106129 a(21)-a(27) by _Lucas A. Brown_, Oct 18 2020 %E A106129 a(1), a(2) by _Lucas A. Brown_, Oct 19 2020