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A145127
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a(n) = 1 + (144 + (50 + (35 + (10 + n)*n)*n)*n)*n/120.
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6
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1, 3, 9, 25, 61, 132, 259, 470, 801, 1297, 2013, 3015, 4381, 6202, 8583, 11644, 15521, 20367, 26353, 33669, 42525, 53152, 65803, 80754, 98305, 118781, 142533, 169939, 201405, 237366, 278287, 324664, 377025, 435931, 501977, 575793, 658045, 749436
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OFFSET
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0,2
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COMMENTS
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(1 + 3x + 9x^2 + ...) = (1 + 3x + 6x^2 + 10x^3 + ...) * (1 + 3x^2 + 6x^3 + 10x^4 + ...). - Gary W. Adamson, Jul 27 2010
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LINKS
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FORMULA
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G.f.: (x^4 - 4*x^3 + 6*x^2 - 3*x + 1) / (1-x)^6.
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MAPLE
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a := n-> 1+ (144+ (50+ (35+ (10+ n) *n) *n) *n) *n/120: seq (a(n), n=0..40);
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PROG
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(Magma) [1 + (144 + (50 + (35 + (10 + n)*n)*n)*n)*n/120: n in [0..40]]; // Vincenzo Librandi, May 19 2011
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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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