%I #6 Jan 15 2023 09:25:52
%S 1,3,21,217,2910,47598,915221,20182962,501463686,13849394018,
%T 420676546425,13933516789491,499667134001968,19284476610918801,
%U 796927418729315367,35106627960374772536,1642235046999495643086,81296320098443729853915,4245930159553383360368993
%N Column 2 of triangle A236961.
%H Paul D. Hanna, <a href="/A236963/b236963.txt">Table of n, a(n) for n = 1..61</a>
%e G.f.: A(x) = x + 3*x^2 + 21*x^3 + 217*x^4 + 2910*x^5 + 47598*x^6 +...
%e Triangle A236961 begins:
%e 1;
%e 1, 1;
%e 4, 2, 1;
%e 27, 11, 3, 1;
%e 256, 94, 21, 4, 1;
%e 3125, 1076, 217, 34, 5, 1;
%e 46656, 15362, 2910, 412, 50, 6, 1;
%e 823543, 262171, 47598, 6333, 695, 69, 7, 1; ...
%e such that column 0 equals A236961(n,0) = n^n.
%e Triangle A236961 transforms diagonals in the table of coefficients in the iterations of G(x), the g.f. of A236960, that starts as:
%e G(x) = x + x^2 + 2*x^3 + 5*x^4 + 16*x^5 + 79*x^6 + 720*x^7 + 10735*x^8 + 211802*x^9 + 4968491*x^10 + 132655760*x^11 + 3943593218*x^12 +...
%Y Cf. A236960, A236961, A236962, A236964.
%K nonn
%O 1,2
%A _Paul D. Hanna_, Feb 10 2014