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A085743
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a(n) = T(n^3) - T(n^2), where T() are the triangular numbers (A000217).
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1
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0, 0, 26, 333, 1944, 7550, 22770, 57771, 129248, 262764, 495450, 879065, 1483416, 2400138, 3746834, 5671575, 8357760, 12029336, 16956378, 23461029, 31923800, 42790230, 56577906, 73883843, 95392224, 121882500, 154237850, 193454001
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OFFSET
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0,3
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LINKS
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FORMULA
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a(n) = (n-1)*n^2*(n^3 + n^2 + 1)/2.
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EXAMPLE
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a(3) = T(3^3) - T(3^2) = T(27) - T(9) = 378 - 45 = 333.
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PROG
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(PARI) t(n)=n*(n+1)/2; for(n=0, 50, print1(t(n^3)-t(n^2)", "))
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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