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Search: id:A104384
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| A104384 |
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Number of distinct partitions of triangular numbers n*(n+1)/2 into (n-2) parts for n>=3. |
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3
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| 1, 4, 12, 27, 57, 110, 201, 352, 598, 984, 1586, 2503, 3882, 5928, 8932, 13287, 19551, 28472, 41078, 58754, 83372, 117417, 164230, 228212, 315190, 432817, 591130, 803192, 1086035, 1461680, 1958596, 2613417, 3473190, 4598073, 6064920, 7971480
(list; graph; listen)
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OFFSET
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3,2
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COMMENT
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In triangle A104382, equals the second diagonal down from the main diagonal.
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PROGRAM
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(PARI) {a(n)=if(n<3, 0, polcoeff(polcoeff( prod(i=1, n*(n+1)/2, 1+y*x^i, 1+x*O(x^(n*(n+1)/2))), n*(n+1)/2, x), n-2, y))}
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CROSSREFS
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Cf. A000009, A104382.
Sequence in context: A104385 A062479 A007009 this_sequence A013697 A064444 A072182
Adjacent sequences: A104381 A104382 A104383 this_sequence A104385 A104386 A104387
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KEYWORD
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nonn
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AUTHOR
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Paul D. Hanna (pauldhanna(AT)juno.com), Mar 04 2005
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