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A112501 Row sums of triangle A112500. 1
1, 2, 6, 23, 108, 601, 3874, 28448, 234903, 2158498, 21883451, 243025718, 2938265815, 38469994687, 542905969228, 8224586470983, 133260591917731, 2301776455966976, 42258406133001866, 822404997883448574 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..19.

FORMULA

a(n) = Sum_{k=1..n+1} A112500(n, k), n >= 0.

G.f: Sum_{n>=1} x^(n-1)/(Product_{k=1..n} (1 - k*x)^(n-k+1)). - Paul D. Hanna, Feb 16 2010

EXAMPLE

Contribution from Paul D. Hanna, Feb 16 2010: (Start)

G.f. A(x) = 1 + 2*x + 6*x^2 + 23*x^3 + 108*x^4 + 601*x^5 + ...

A(x) = 1/(1-x) + x/[(1-x)^2*(1-2x)] + x^2/[(1-x)^3*(1-2x)^2*(1-3x)] + ... (End)

PROG

(PARI) {a(n)=polcoeff(sum(m=1, 16, x^(m-1)/prod(k=1, m, (1-k*x +x*O(x^n))^(m-k+1))), n)} \\ Paul D. Hanna, Feb 16 2010

CROSSREFS

Sequence in context: A155857 A071076 A297196 * A093345 A289681 A002136

Adjacent sequences:  A112498 A112499 A112500 * A112502 A112503 A112504

KEYWORD

nonn,easy

AUTHOR

Wolfdieter Lang, Oct 14 2005

STATUS

approved

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Last modified September 22 22:38 EDT 2021. Contains 347609 sequences. (Running on oeis4.)