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 A124551 #3 Mar 30 2012 18:37:01
%S A124551 1,1,2,5,16,66,348,2321,19437,203554,2661035,43399794,883165898,
%T A124551 22436796424,712153021345,28264751131084,1403965520612428,
%U A124551 87352867349503436,6813355443494722779,666712967112785700169
%N A124551 Row 1 of tables A124550 and A124560; also equals the antidiagonal sums of table A124550.
%C A124551 In table A124550, the g.f. of row n, R_n(y), simultaneously satisfies: R_n(y) = [ Sum_{k>=0} y^k * R_{n*k}(y) ]^n for n>=0.
%F A124551 G.f.: A(x) = Sum_{k>=0} y^k * R_{k}(y), where R_n(x) is the g.f. of row n in table A124550.
%Y A124551 Cf. A124550, A124560; other rows: A124552, A124553, A124554, A124555, A124556.
%K A124551 nonn
%O A124551 0,3
%A A124551 _Paul D. Hanna_, Nov 07 2006