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 A286786 #12 May 17 2017 22:53:03
%S A286786 1,9,91,1063,14193,213953,3602891,67168527,1375636129,30741614905,
%T A286786 745133551611,19485223248311,547092691302545,16422216867929457,
%U A286786 524970306508659691,17809453107819266335,639153386976421052481,24196474723945543441769,963736849031626750711451,40289411871795861783689799
%N A286786 Column 1 of A286781.
%H A286786 Gheorghe Coserea, <a href="/A286786/b286786.txt">Table of n, a(n) for n = 1..210</a>
%o A286786 (PARI)
%o A286786 A286781_ser(N, t='t) = {
%o A286786 my(x='x+O('x^N), y0=1+O('x^N), y1=0, n=1);
%o A286786 while(n++,
%o A286786 y1 = (1 + x*y0 + 2*x^2*y0')*(1 - x*y0*(1-t))/(1-x*y0)^2;
%o A286786 if (y1 == y0, break()); y0 = y1;);
%o A286786 y0;
%o A286786 };
%o A286786 Kol(K,N=20) = {
%o A286786 my(s = A286781_ser(N+K, 't+O('t^(K+1))));
%o A286786 vector(N, n, polcoeff(polcoeff(s, K+n-1), K));
%o A286786 };
%o A286786 Kol(1)
%Y A286786 Cf. A286781.
%K A286786 nonn
%O A286786 1,2
%A A286786 _Gheorghe Coserea_, May 16 2017