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A093887 a(n) = A093886(n)/(1!*2!*3!*...*n!). 1
1, 1, 2, 140, 105, 840840, 51051, 79755701025, 143400750442950, 122535439350874224675, 46705681584242830001657805, 65358008635496174751045143339993779875 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..12.

EXAMPLE

a(4) = 140 = 8! /(1!*2!*3!*4!) = 40320/288.

MAPLE

a:=proc(n) local A, k: A:={}: for k from 1 to n*(n+1)/2 do if type(k!/product(j!, j=1..n), integer)=true then A:=A union {k} else A:=A fi od: A[1]!/product(i!, i=1..n); end: seq(a(n), n=1..14); # not necessarily the best Maple program # Emeric Deutsch, Feb 03 2006

CROSSREFS

Cf. A093886.

Sequence in context: A094482 A265176 A101232 * A152005 A140898 A220513

Adjacent sequences:  A093884 A093885 A093886 * A093888 A093889 A093890

KEYWORD

nonn

AUTHOR

Amarnath Murthy, Apr 23 2004

EXTENSIONS

More terms from Emeric Deutsch, Feb 03 2006

STATUS

approved

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Last modified December 2 07:33 EST 2021. Contains 349437 sequences. (Running on oeis4.)