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 A356755 #45 Oct 15 2022 16:29:04 %S A356755 4,6,10,119,155,158,215,27682,3066887,3066907,3067027,3067167,3067187, %T A356755 3067247,3067277,3067682,3067687,3067742,3067787,3067847,3067907, %U A356755 3067917,3067937,3067942,3068042,3068067,348933302,348933422,44690978131,44690978257,44690978537,44690978719,44690978971 %N A356755 Semiprimes k such that k is congruent to 2 modulo k's index in the sequence of semiprimes. %C A356755 a(34) > 8040423200947. %H A356755 Lucas A. Brown, <a href="https://github.com/lucasaugustus/oeis/blob/main/semiprimemods.py">semiprimemods.py</a> %F A356755 a(n) = A001358(A106127(n)). %e A356755 The 1st semiprime is 4, which is congruent to 2 (mod 1), so 4 is in the sequence. %e A356755 The 2nd semiprime is 6, which is congruent to 2 (mod 2), so 6 is in the sequence. %e A356755 The 3rd semiprime is 9, which is congruent to 0 (mod 3), so 9 is not in the sequence. %e A356755 The 4th semiprime is 10, which is congruent to 2 (mod 4), so 10 is in the sequence. %Y A356755 Cf. A001358, A106127. %K A356755 nonn,hard %O A356755 1,1 %A A356755 _Lucas A. Brown_, Oct 13 2022