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A005460
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(3*n+4)*(n+3)!/24.
(Formerly M4433)
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4
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1, 7, 50, 390, 3360, 31920, 332640, 3780000, 46569600, 618710400, 8821612800, 134399865600, 2179457280000, 37486665216000, 681734237184000, 13071512982528000
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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REFERENCES
| R. K. Guy, personal communication.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
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LINKS
| Vincenzo Librandi, Table of n, a(n) for n = 0..300
Milan Janjic, Enumerative Formulas for Some Functions on Finite Sets
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FORMULA
| Expansion of (1+2x) / (1-x)^5.
Essentially Stirling numbers of second kind - see A028246.
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PROG
| (MAGMA) [(3*n+4)*Factorial(n+3)/24: n in [0..20]]; // Vincenzo Librandi, Oct 08 2011
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CROSSREFS
| Sequence in context: A081189 A108869 A065429 * A053155 A197570 A204463
Adjacent sequences: A005457 A005458 A005459 * A005461 A005462 A005463
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KEYWORD
| nonn,easy
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AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com).
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