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 A019307 #14 Jun 12 2022 14:06:56 %S A019307 0,1,2,3,8,9,144,145,167,627,2677,2725,2726,12071,48652,206025, %T A019307 63331966,307304209,1357691960 %N A019307 First time that the Grundy function G(x) for "subtract-a-Fibonacci-number" takes the value n. %C A019307 See Rouse Ball and Coxeter for "subtract-a-square". %D A019307 W. W. Rouse Ball and H. S. M. Coxeter, Mathematical Recreations and Essays, 12th Edition. %H A019307 Rémy Sigrist, <a href="/A019307/a019307.txt">C program</a> %o A019307 (C) See Links section. %Y A019307 Cf. A014588, A297963. %K A019307 nonn,more %O A019307 0,3 %A A019307 Torsten Sillke (sillke(AT)lh-systems.de) %E A019307 a(17) from _Pontus von Brömssen_, Jun 06 2022 %E A019307 a(18) from _Rémy Sigrist_, Jun 12 2022