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A114806
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Nonuple factorial, 9-factorial, n!9, n!!!!!!!!!.
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3
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1, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 22, 36, 52, 70, 90, 112, 136, 162, 190, 440, 756, 1144, 1610, 2160, 2800, 3536, 4374, 5320, 12760, 22680, 35464, 51520, 71280, 95200, 123760, 157464, 196840, 484880, 884520, 1418560, 2112320, 2993760, 4093600
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,3
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LINKS
| Eric Weisstein's World of Mathematics, Multifactorial.
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FORMULA
| a(0) = 1, a(n) = n for 1<=n<=9, a(n) = n*a(n-9) for n>=10.
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EXAMPLE
| a(10) = 10 * a(10-9) = 10 * a(1) = 10 * 1 = 10.
a(20) = 20 * a(20-9) = 20 * a(11) = 20 * (11*a(11-9)) = 20 * 11 * a(2) = 20 * 11 * 2 = 440.
a(30) = 30 * a(30-9) = 30 * a(21) = 30 * (21*a(21-9)) = 30 * 21 * a(12) = 30 * 21 * (12*a(12-9)) = 30 * 21 * 12 * 3 = 22680.
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MATHEMATICA
| NFactorialM[n_, m_] := Block[{k = n, p = Max[1, n]}, While[k > m, k -= m; p *= k]; p]; Array[ NFactorialM[#, 9] &, 44, 0] (* Robert G. Wilson v, May 10 2011 *)
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CROSSREFS
| Cf. A000142, A006882, A007661, A007662, A085157, A085158.
Sequence in context: A081511 A030283 A179310 * A039229 A054659 A120125
Adjacent sequences: A114803 A114804 A114805 * A114807 A114808 A114809
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KEYWORD
| easy,nonn
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AUTHOR
| Jonathan Vos Post (jvospost3(AT)gmail.com), Feb 19 2006
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