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A085158
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Sextuple factorials, 6-factorials, n!!!!!!, n!6.
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10
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1, 1, 2, 3, 4, 5, 6, 7, 16, 27, 40, 55, 72, 91, 224, 405, 640, 935, 1296, 1729, 4480, 8505, 14080, 21505, 31104, 43225, 116480, 229635, 394240, 623645, 933120, 1339975, 3727360, 7577955, 13404160, 21827575, 33592320, 49579075, 141639680
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,3
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COMMENTS
| The term "Sextuple factorial numbers" is also used for the sequences A008542, A008543, A011781, A047058, A047657, A049308, which have a different definition. The definition given here is the one commonly used.
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LINKS
| Eric Weisstein's World of Mathematics, Multifactorial Section of World of Mathematics.
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FORMULA
| a(n)=1 for n<1 otherwise a(n)=n*a(n-6)
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EXAMPLE
| a(14)=224 because 14*a(14-6)=14*a(8)=14*16=224.
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CROSSREFS
| Cf. n!:A000142, n!!:A006882, n!!!:A007661, n!!!!:A007662, n!!!!!:A085157, 6-factorial primes: n!!!!!!+1:A085150, n!!!!!!-1:A051592.
Sequence in context: A132028 A193551 A069188 * A065639 A171678 A039090
Adjacent sequences: A085155 A085156 A085157 * A085159 A085160 A085161
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KEYWORD
| nonn
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AUTHOR
| Hugo Pfoertner (hugo(AT)pfoertner.org), Jun 21 2003
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