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A186030
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a(n) = n*(13*n-3)/2.
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8
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0, 5, 23, 54, 98, 155, 225, 308, 404, 513, 635, 770, 918, 1079, 1253, 1440, 1640, 1853, 2079, 2318, 2570, 2835, 3113, 3404, 3708, 4025, 4355, 4698, 5054, 5423, 5805, 6200, 6608, 7029, 7463, 7910, 8370, 8843, 9329, 9828, 10340, 10865, 11403
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OFFSET
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0,2
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LINKS
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FORMULA
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G.f.: x*(5+8*x)/(1-x)^3.
E.g.f.: (1/2)*(13*x^2 + 10*x)*exp(x). - G. C. Greubel, Jul 17 2017
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MATHEMATICA
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PROG
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(Magma) [ n*(13*n-3)/2 : n in [0..42] ];
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CROSSREFS
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Cf. numbers of the form n*(d*n+10-d)/2 indexed in A140090.
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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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