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A007235 Structure constants for certain representations of S_n.
(Formerly M4500)
0
8, 27, 384, 12100, 736128, 70990416, 9939419136, 1896254551296, 472882821120000, 149328979405056000, 58255835226557644800, 27519543889780053196800, 15483244831426302168268800, 10231838708930053383168000000 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

REFERENCES

A. Goupil, Decomposition of certain products of conjugacy classes of S_n, J. Combin. Theory, A 66 (1994), 102-117.

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..14.

FORMULA

a(n) = b(n, 2*n+2) where b(k, m) = (2 * m! / (k^2 * (m-k)^2)) * ((m / (m+1)) * (1 + (-1)^(k+1) / binomial(m, k)) + ((k+1) / binomial(m, k)) * Sum_{j=0..k-1} (j+1) / (binomial(k - 1, j) * binomial(k, j))) [from Goupil]. - Sean A. Irvine, Nov 23 2017

CROSSREFS

Sequence in context: A115694 A028935 A030089 * A029789 A155930 A100519

Adjacent sequences:  A007232 A007233 A007234 * A007236 A007237 A007238

KEYWORD

nonn

AUTHOR

Simon Plouffe

EXTENSIONS

More terms from Sean A. Irvine, Nov 23 2017

STATUS

approved

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Last modified December 17 09:43 EST 2018. Contains 318193 sequences. (Running on oeis4.)