

A060603


Number of ways of expressing an ncycle in the symmetric group S_n as a product of n+1 transpositions.


1



0, 1, 27, 640, 15625, 408240, 11529602, 352321536, 11622614670, 412500000000, 15692141883605, 637501182050304, 27561634699895023, 1263990776407224320, 61305144653320312500, 3135946492530623774720, 168757013424812699892108
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OFFSET

1,3


COMMENTS

For n >= 3, a(n) = A060348(n)*n. The number of ways of expressing an ncycle in the symmetric group S_n as a product of n1 transpositions was given in the comment to A000272.


LINKS

Harry J. Smith, Table of n, a(n) for n = 1..200
D. M. Jackson, Some Combinatorial Problems Associated with Products of Conjugacy Classes of the Symmetric Group, Journal of Combinatorial Theory, Series A, 49 363369(1988).


FORMULA

a(n) = (1/24) * (n^2  1) * n^(n + 1).


EXAMPLE

a(2) = 1 because in S_2 the only way to write (12) as a product of 3 transpositions is (12) = (12)(12)(12).


MAPLE

for n from 1 to 30 do printf(`%d, `, 1/24 * (n^2  1) * n^(n + 1)) od:


PROG

(PARI) a(n)={(n^2  1) * n^(n + 1)/24} \\ Harry J. Smith, Jul 07 2009


CROSSREFS

Cf. A060348, A000272.
Sequence in context: A231292 A046359 A223500 * A116988 A113364 A095898
Adjacent sequences: A060600 A060601 A060602 * A060604 A060605 A060606


KEYWORD

nonn


AUTHOR

Dan Fux (dan.fux(AT)OpenGaia.com or danfux(AT)OpenGaia.com), Apr 13 2001


EXTENSIONS

More terms from James A. Sellers, Apr 13 2001


STATUS

approved



