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A090115 a(n)=Product[p(n)-j, j=1..n]/n!=A090114(n)/n!. 0
1, 1, 4, 15, 252, 924, 11440, 43758, 497420, 13123110, 54627300, 1251677700, 12033222880, 52860229080, 511738760544, 10363194502115, 197548686920970, 925029565741050, 17302625882942400, 161884603662657876 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

It needs proof that A090114(n) is always divisible by n!, that is, these terms are integers.

LINKS

Table of n, a(n) for n=1..20.

EXAMPLE

n=5: p(5)=11, a(5)=(11-1)()(11-2)(11-3)(11-4)(11-5)/5!= 10.9.8.7.6/120=30240=252

MATHEMATICA

Table[Apply[Times, Table[Prime[w]-j, {j, 1, w}]]/w!, {w, 1, 15}]

CROSSREFS

Cf. A000142, A090114.

Sequence in context: A118908 A153060 A139244 * A051999 A048731 A000881

Adjacent sequences:  A090112 A090113 A090114 * A090116 A090117 A090118

KEYWORD

nonn

AUTHOR

Labos Elemer, Jan 08 2004

STATUS

approved

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Last modified May 20 12:33 EDT 2019. Contains 323422 sequences. (Running on oeis4.)