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A051232
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9-factorial numbers.
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10
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1, 9, 162, 4374, 157464, 7085880, 382637520, 24106163760, 1735643790720, 140587147048320, 12652843234348800, 1252631480200531200, 135284199861657369600, 15828251383813912243200
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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COMMENTS
| For n >= 1 a(n) is the order of the wreath product of the symmetric group S_n and the Abelian group (C_9)^n. - Ahmed Fares (ahmedfares(AT)my-deja.com), May 07 2001
a(n) = 8*A035023(n) = product(9*k,k=1..n), n >= 1; a(0) := 1.
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LINKS
| Vincenzo Librandi, Table of n, a(n) for n = 0..300
Index entries for sequences related to factorial numbers
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FORMULA
| a(n) = n!*9^n =: (9*n)(!^9);
E.g.f. 1/(1-9*x)
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MAPLE
| with(combstruct):A:=[N, {N=Cycle(Union(Z$9))}, labeled]: seq(count(A, size=n)/9, n=1..14); - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Dec 05 2007
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MATHEMATICA
| s=1; lst={s}; Do[s+=n*s; AppendTo[lst, s], {n, 8, 2*5!, 9}]; lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Nov 08 2008]
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PROG
| (MAGMA) [9^n*Factorial(n): n in [0..20]]; // Vincenzo Librandi, Oct 05 2011
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CROSSREFS
| A047058, A051188, A051189. a(n) = A051231(n-1, 0), A053116. (first column of triangle).
Sequence in context: A157553 A202438 A156273 * A157574 A077280 A041147
Adjacent sequences: A051229 A051230 A051231 * A051233 A051234 A051235
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KEYWORD
| easy,nonn
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AUTHOR
| Wolfdieter Lang (wolfdieter.lang(AT)physik.uni-karlsruhe.de)
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