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A171509 Riordan array (f(x), x*f(x)) where f(x) is the g.f. of A126931. 0
1, 3, 1, 10, 6, 1, 33, 29, 9, 1, 110, 126, 57, 12, 1, 366, 518, 306, 94, 15, 1, 1220, 2052, 1494, 600, 140, 18, 1, 4065, 7925, 6849, 3389, 1035, 195, 21, 1, 13550, 30030, 30025, 17628, 6635, 1638, 259, 24, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Equal to A053121*B^3, B = A007318.

LINKS

Table of n, a(n) for n=0..44.

FORMULA

Sum_[k, 0<=k<=n} T(n,k)*x^k = A126930(n), A126120(n), A001405(n), A054341(n), A126931(n) for x = -4, -3, -2, -1, 0 respectively.

T(n,k) = T(n-1,k-1) + 3*T(n-1,k) + sum_{i, i>=0} T(n-1,k+1+i)*(-3)^i. - Philippe Deléham, Feb 23 2012

EXAMPLE

Triangle begins : 1 ; 3,1 ; 10,6,1 ; 33,29,9,1 ; 110,126,57,12,1 ; ...

CROSSREFS

Cf. A053121, A054336, A096164, A171505

Sequence in context: A113187 A057967 A132964 * A171505 A134283 A035324

Adjacent sequences:  A171506 A171507 A171508 * A171510 A171511 A171512

KEYWORD

nonn,tabl

AUTHOR

Philippe Deléham, Dec 10 2009

STATUS

approved

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Last modified December 10 09:41 EST 2016. Contains 278999 sequences.