A187118 - OEIS

A187118

Rows sums of triangle A187115.

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

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OFFSET

2,2

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.

LINKS

Table of n, a(n) for n=2..19.

PROG

(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)}

CROSSREFS

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

Sequence in context: A294202 A107103 A107887 * A121812 A039750 A365655

Adjacent sequences: A187115 A187116 A187117 * A187119 A187120 A187121

KEYWORD

nonn

AUTHOR

Paul D. Hanna, Mar 08 2011

STATUS

approved