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A159605 E.g.f: Sum_{n>=1} a(n)*x^(2n-1)/(2n-1)! = Series_Reversion of e.g.f. S(x) of A159601. 0
1, 3, 63, 3465, 363825, 62214075, 15740160975, 5524796502225, 2569030373534625, 1528573072253101875, 1132672646539548489375, 1022803399825212285905625, 1105650475211054481063980625, 1409704355894094463356575296875 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..14.

FORMULA

a(n) = Product_{k=1..n} (2k-3)(4k-5).

EXAMPLE

E.g.f.: A(x) = x + 3*x^3/3! + 63*x^5/5! + 3465*x^7/7! +...

A(S(x)) = x where S(x) = Sum_{n>=1} A159601(n)*x^(2n-1)/(2n-1)! :

S(x) = x - 3*x^3/3! + 27*x^5/5! - 441*x^7/7! + 11529*x^9/9! +...

PROG

(PARI) a(n)=prod(k=1, n, (2*k-3)*(4*k-5))

CROSSREFS

Cf. A159601.

Sequence in context: A133275 A258657 A123687 * A180761 A156904 A193100

Adjacent sequences:  A159602 A159603 A159604 * A159606 A159607 A159608

KEYWORD

nonn

AUTHOR

Paul D. Hanna, May 11 2009

STATUS

approved

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Last modified May 24 06:53 EDT 2019. Contains 323529 sequences. (Running on oeis4.)