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A001756 Expansion of an integral.
(Formerly M4967 N2131)
1
15, 60, 450, 4500, 55125, 793800, 13097700, 243243000, 5016886875, 113716102500, 2808787731750, 75071235739500, 2158298027510625, 66409170077250000, 2177272076104125000, 75769068248423550000, 2789248824895091934375, 108288483790044745687500 (list; graph; refs; listen; history; text; internal format)
OFFSET

3,1

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

T. D. Noe, Table of n, a(n) for n = 3..100

FORMULA

a(n) = 5*A007531(n)*A001147(n-2)/(2*(2*n-5)). - Philippe Deléham, Jun 26 2006

a(3) = 15, a(n) = a(n-1)*n*(2*n-7)/(n-3). - Philippe Deléham, Sep 19 2006

MATHEMATICA

RecurrenceTable[{a[3]==15, a[n]==a[n-1]n (2n-7)/(n-3)}, a, {n, 20}] (* Harvey P. Dale, Nov 08 2011 *)

Join[{c = 15}, Table[c = c*n*(2*n - 7)/(n - 3), {n, 4, 20}]] (* T. D. Noe, Aug 10 2012 *)

CROSSREFS

Sequence in context: A223337 A110755 A206231 * A284096 A022288 A041432

Adjacent sequences:  A001753 A001754 A001755 * A001757 A001758 A001759

KEYWORD

nonn

AUTHOR

N. J. A. Sloane

EXTENSIONS

More terms from Philippe Deléham, Sep 19 2006

Corrected and extended by Harvey P. Dale, Nov 08 2011

STATUS

approved

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Last modified February 21 20:24 EST 2020. Contains 332111 sequences. (Running on oeis4.)