A187118 Rows sums of triangle A187115.

1, 3, 12, 67, 512, 5143, 64988, 995334, 17948683, 372703529, 8759307844, 229843336284, 6660078541359, 211201170221925, 7274712426981184, 270441300892307916, 10791919593795653296, 460087687818627367809

Offset: 2

Author

Paul D. Hanna, Mar 08 2011

Keywords

• nonn

Comments

Definition of triangle: A187115(n,k) = [y^k] R_{n-1}(y+y^2) for k=2..n, n>2, where R_n(y) is the n-th row polynomial starting with R_2(y)=y^2.

Crossrefs

Cf. A187115, A135082, A187116, A187117, A187008.

Programs

PARI

{a(n)=local(Rn=y^2);for(m=2,n,Rn=subst(truncate(Rn),y,y+y^2+O(y^m)));subst(truncate(Rn),y,1)}