A113596 P(P(n))-P(P(n-1)), where P(n) = n(n+1)(n+2)/6 (cf. A000292).

0, 1, 19, 200, 1320, 6230, 23086, 71484, 192900, 467115, 1036585, 2140996, 4164524, 7698600, 13623260, 23210440, 38252856, 61222389, 95462175, 145416880, 216905920, 317444666, 456618954, 646518500, 902235100, 1242431775, 1689989301, 2272736844

Offset

0,3

Links

Table of n, a(n) for n=0..27.

Formula

From Chai Wah Wu, May 28 2016 : (Start)

a(n) = 9*a(n-1) - 36*a(n-2) + 84*a(n-3) - 126*a(n-4) + 126*a(n-5) - 84*a(n-6) + 36*a(n-7) - 9*a(n-8) + a(n-9)

G.f.: x*(4*x^5 + 80*x^4 + 120*x^3 + 65*x^2 + 10*x + 1)/(1 - x)^9 (End)

Prog

(PARI) P(n) =  n*(n+1)*(n+2)/6;
a(n) = P(P(n)) - P(P(n-1)); \\ Michel Marcus, Sep 16 2013

Crossrefs

Cf. A000292, A111400.

Sequence in context: A241021 A055558 A160452 * A155670 A085770 A002501

Adjacent sequences: A113593 A113594 A113595 * A113597 A113598 A113599

Keyword

easy,nonn

Author

Amarnath Murthy, Nov 07 2005

Extensions

Better description from Jonathan Vos Post, Nov 11 2005

Edited by N. J. A. Sloane, Nov 11, 2005

Status

approved