A364630 G.f. satisfies A(x) = (1+x*A(x)^4)/(1-x)^2.
1, 3, 17, 153, 1621, 18732, 229103, 2915498, 38204497, 512027945, 6985933889, 96705749625, 1354868839933, 19175008086962, 273731258980839, 3936883123412972, 56991044183321197, 829750943505927435, 12142121554514962205, 178488780583916045949
Offset: 0
Keywords
Programs
-
PARI
a(n) = sum(k=0, n, binomial(n+7*k+1, 8*k+1)*binomial(4*k, k)/(3*k+1));
Formula
a(n) = Sum_{k=0..n} binomial(n+7*k+1,8*k+1) * binomial(4*k,k) / (3*k+1).