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A001757 Expansion of an integral: central elements of rows of triangle in A059366.
(Formerly M1941 N0769)
3
1, 2, 9, 54, 450, 4500, 55125, 771750, 12502350, 225042300, 4538353050, 99843767100, 2410513805700, 62673358948200, 1762688220418125, 52880646612543750, 1698056319002793750, 57733914846094987500, 2084194325944029048750 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

REFERENCES

L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 167.

N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

LINKS

Table of n, a(n) for n=1..19.

FORMULA

a(n)=A000984(n/2)^2*A000142(n)/A000079(n)

CROSSREFS

Sequence in context: A254795 A064151 A075679 * A267225 A078455 A036074

Adjacent sequences:  A001754 A001755 A001756 * A001758 A001759 A001760

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Larry Reeves (larryr(AT)acm.org), Feb 08 2001

Corrected and extended by Sean A. Irvine, Nov 19 2012

STATUS

approved

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Last modified November 18 18:20 EST 2018. Contains 317324 sequences. (Running on oeis4.)