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 A250217 #30 Dec 17 2022 08:24:55
%S A250217 1,11,18,23,25,37,68,113,115,179,229,421,545,1129,1451,1481,1847,1987,
%T A250217 3099,3329,4391
%N A250217 Numbers k such that A085398(k) sets a new record value.
%C A250217 Record values at positions A085398(a(n)): {3, 5, 6, 10, 22, 61, 85, 86, 268, 304, 606, 808, ...}. - _Michael De Vlieger_, May 20 2017
%t A250217 Function[s, Function[t, Map[Position[s, #][[1, 1]] &, t]]@ Union@ FoldList[Max, s]]@ Table[k = 2; While[! PrimeQ[Cyclotomic[n, k]], k++]; k, {n, 500}] (* _Michael De Vlieger_, May 20 2017, after _Eric Chen_ at A085398 *)
%Y A250217 Cf. A085398, A250218.
%K A250217 nonn,more
%O A250217 1,2
%A A250217 _Eric Chen_, Dec 24 2014
%E A250217 Corrected by insertion of 421. - _Robert G. Wilson v_, May 19 2017
%E A250217 a(17)-a(21) from _Jinyuan Wang_, Dec 17 2022