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A262872
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Expansion of (Sum_{i>=0} x^(i^2)) * (Sum_{j>=0} x^(j^3)) / (1-x).
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1
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1, 3, 4, 4, 5, 6, 6, 6, 7, 9, 10, 10, 11, 11, 11, 11, 12, 14, 14, 14, 14, 14, 14, 14, 15, 16, 17, 18, 19, 19, 19, 20, 20, 21, 21, 21, 23, 24, 24, 24, 24, 24, 24, 25, 26, 26, 26, 26, 26, 27, 28, 28, 29, 29, 29, 29, 29, 30, 30, 30, 30, 30, 30, 31, 32, 33, 33, 33, 34, 34, 34
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OFFSET
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0,2
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COMMENTS
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a(n) is number of nonnegative integer solutions (x,y,z) such that x + y^2 + z^3 = n.
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LINKS
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FORMULA
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G.f.: (Sum_{i>=0} x^(i^2)) * (Sum_{j>=0} x^(j^3)) / (1-x).
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EXAMPLE
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a(4) = 5 because there are 5 solutions: (5,0,0), (4,1,0), (4,0,1), (3,1,1) and (1,2,0).
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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