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A051581 (2*n+7)!!/7!!, related to A001147 (odd double factorials). 1
1, 9, 99, 1287, 19305, 328185, 6235515, 130945815, 3011753745, 75293843625, 2032933777875, 58955079558375, 1827607466309625, 60311046388217625, 2110886623587616875, 78102805072741824375, 3046009397836931150625 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

COMMENTS

Row m=7 of the array A(3; m,n) := (2*n+m)!!/m!!, m >= 0, n >= 0.

FORMULA

a(n) = (2*n+7)!!/7!!; e.g.f.: 1/(1-2*x)^(9/2).

MAPLE

with(finance):seq(mul(cashflows([k, k, 1], 0), k=4..n), n=3..22); # [From Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Dec 22 2008]

CROSSREFS

Cf. A000165, A001147(n+1), A002866(n+1), A051577-A051580 (rows m=0..6).

Sequence in context: A103456 A155157 A015685 * A080291 A113395 A070068

Adjacent sequences:  A051578 A051579 A051580 * A051582 A051583 A051584

KEYWORD

easy,nonn

AUTHOR

Wolfdieter Lang (wolfdieter.lang(AT)physik.uni-karlsruhe.de)

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Last modified February 16 07:10 EST 2012. Contains 205874 sequences.