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A104394
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Sums of 4 distinct positive pentatope numbers (A000332).
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6
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56, 91, 111, 121, 125, 147, 167, 177, 181, 202, 212, 216, 231, 232, 236, 246, 251, 261, 265, 286, 296, 300, 316, 320, 330, 342, 351, 352, 356, 371, 372, 376, 381, 385, 386, 406, 407, 411, 416, 420, 421, 436, 440, 441, 450, 462, 472, 476, 492, 496
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OFFSET
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1,1
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COMMENTS
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Pentatope number Ptop(n) = binomial(n+3,4) = n*(n+1)*(n+2)*(n+3)/24. Hyun Kwang Kim asserts that every positive integer can be represented as the sum of no more than 8 pentatope numbers; but in this sequence we are only concerned with sums of nonzero distinct pentatope numbers.
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REFERENCES
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Conway, J. H. and Guy, R. K. The Book of Numbers. New York: Springer-Verlag, pp. 55-57, 1996.
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LINKS
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FORMULA
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a(n) = Ptop(h) + Ptop(i) + Ptop(j) + Ptop(k) for some positive h=/=i=/=j=/=k and Ptop(n) = binomial(n+3,4).
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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