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 A056580 #15 Jun 04 2018 17:53:44
%S A056580 1,23,85,231,535,1124,2198,4072,7228,12392,20632,33506,53252,83048,
%T A056580 127359,192401,286751,422151,614552,885480,1263795,1787960,2508952,
%U A056580 3493970,4831164,6635624,9056943,12288744,16580631,22253151,29716459
%N A056580 a(n) = round(e^(Pi*sqrt(n))).
%H A056580 Seiichi Manyama, <a href="/A056580/b056580.txt">Table of n, a(n) for n = 0..200</a>
%o A056580 (PARI) {a(n) = round(exp(Pi*sqrt(n)))} \\ _Seiichi Manyama_, Jun 04 2018
%Y A056580 Cf. A019296, A019297, A035484, A056581.
%K A056580 nonn
%O A056580 0,2
%A A056580 _Henry Bottomley_, Jun 30 2000
%E A056580 Definition corrected by _Michael Somos_, Sep 15 2008