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A069906
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Number of pentagons that can be formed with perimeter n. In other words, partitions of n into five parts such that the sum of any four is more than the fifth.
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6
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0, 0, 0, 0, 0, 1, 1, 2, 2, 4, 5, 8, 9, 14, 16, 23, 25, 35, 39, 52, 57, 74, 81, 103, 111, 139, 150, 184, 197, 239, 256, 306, 325, 385, 409, 480, 507, 590, 623, 719, 756, 867, 911, 1038, 1087, 1232, 1289, 1453, 1516, 1701, 1774, 1981, 2061, 2293
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,8
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REFERENCES
| G. E. Andrews, P. Paule and A. Riese, MacMahon's Partition Analysis IX: k-gon partitions, Bull. Austral Math. Soc., 64 (2001), 321-329.
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LINKS
| T. D. Noe, Table of n, a(n) for n=0..1000
G. E. Andrews, P. Paule and A. Riese, MacMahon's partition analysis III. The Omega package, p. 19.
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FORMULA
| G.f.: x^5*(1-x^11)/((1-x)*(1-x^2)*(1-x^4)*(1-x^5)*(1-x^6)*(1-x^8)).
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MATHEMATICA
| CoefficientList[Series[x^5(1-x^11)/((1-x)(1-x^2)(1-x^4)(1-x^5)(1-x^6) (1-x^8)), {x, 0, 60}], x] (* From Harvey P. Dale, Dec 16 2011 *)
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CROSSREFS
| Cf. A005044, A062890, A069907.
Sequence in context: A034398 A027069 A166515 * A183564 A053097 A035946
Adjacent sequences: A069903 A069904 A069905 * A069907 A069908 A069909
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KEYWORD
| nonn,easy
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AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com), May 05, 2002
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