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 A077624 #19 Apr 24 2022 06:35:52
%S A077624 2,4,0,8,10,16,22,32,44,64,90,128,180,256,362,512,724,1024,1448,2048,
%T A077624 2896,4096,5792,8192,11584,16384,23170,32768,46340,65536,92680,131072,
%U A077624 185362,262144,370726,524288,741454,1048576,1482910,2097152,2965820,4194304,5931640
%N A077624 Largest term in periodic part of continued fraction expansion of square root of 2^n + 1 or 0 if 2^n + 1 is a square.
%C A077624 a(n) = 0 iff n = 3, as a consequence of Catalan's conjecture or Mihăilescu's theorem. - _Bernard Schott_, Apr 22 2022
%H A077624 Chai Wah Wu, <a href="/A077624/b077624.txt">Table of n, a(n) for n = 1..78</a>
%H A077624 Wikipedia, <a href="https://en.wikipedia.org/wiki/Catalan's_conjecture">Catalan's conjecture</a>.
%t A077624 Table[Max[Last[ContinuedFraction[Sqrt[1+2^u]]]], {u, 1, 32}]
%Y A077624 Cf. A077625-A077635.
%K A077624 nonn
%O A077624 1,1
%A A077624 _Labos Elemer_, Nov 13 2002
%E A077624 Definition clarified, a(3) corrected and a(33)-a(43) added by _Chai Wah Wu_, Apr 19 2022