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A068236
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First differences of (n+1)^5-n^5.
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4
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30, 180, 570, 1320, 2550, 4380, 6930, 10320, 14670, 20100, 26730, 34680, 44070, 55020, 67650, 82080, 98430, 116820, 137370, 160200, 185430, 213180, 243570, 276720, 312750, 351780, 393930, 439320, 488070, 540300, 596130, 655680, 719070, 786420, 857850, 933480
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,1
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COMMENTS
| For n>=0, a(n) is equal to the number of functions f:{1,2,3,4,5}->{1,2,...,n+2} such that Im(f) contains 2 fixed elements. - Aleksandar M. Janjic and Milan R. Janjic (agnus(AT)blic.net), Feb 24 2007
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LINKS
| Milan Janjic, Enumerative Formulas for Some Functions on Finite Sets
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FORMULA
| a(n)=(n+2)^5-2*(n-1)^5+n^5
a(n)=30*A005900(n+1). [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Sep 02 2008]
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MATHEMATICA
| Table[20*n^3 + 10*n, {n, 1, 100}] (* From Vladimir Joseph Stephan Orlovsky, Jun 19 2011 *)
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CROSSREFS
| Cf. A022521, A000584.
Sequence in context: A100430 A159653 A101098 * A054559 A042756 A156318
Adjacent sequences: A068233 A068234 A068235 * A068237 A068238 A068239
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KEYWORD
| nonn
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AUTHOR
| Eli McGowan (ejmcgowa(AT)mail.lakeheadu.ca), Mar 25 2002
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