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 A355556 #9 Jul 09 2022 15:30:52 %S A355556 0,1,2,6,5050,5056,5064,40520,40696,630373,40348521,483383076, %T A355556 6302798387 %N A355556 a(n) is the smallest position in the subtract-a-factorial game for which the value of the Sprague-Grundy function (or nim-value) is n. %H A355556 Rémy Sigrist, <a href="/A355556/a355556.txt">C program</a> %e A355556 a(3) = 6, because the smallest k for which A014587(k) = 3 is k = 6. %o A355556 (C) See Links section. %Y A355556 Cf. A014587, A019307, A297963, A355557. %K A355556 nonn,more %O A355556 0,3 %A A355556 _Pontus von Brömssen_, Jul 09 2022 %E A355556 a(11)-a(12) from _Rémy Sigrist_, Jul 09 2022