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A217947
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a(n) = (n+1)*(n^3+15*n^2+74*n+132)/12.
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1
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11, 37, 87, 172, 305, 501, 777, 1152, 1647, 2285, 3091, 4092, 5317, 6797, 8565, 10656, 13107, 15957, 19247, 23020, 27321, 32197, 37697, 43872, 50775, 58461, 66987, 76412, 86797, 98205, 110701, 124352, 139227, 155397, 172935, 191916, 212417, 234517, 258297, 283840, 311231
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OFFSET
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0,1
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LINKS
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FORMULA
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a(n) = 5*a(n-1)-10*a(n-2)+10*a(n-3)-5*a(n-4)+a(n-5) n>4. - Vincenzo Librandi, Dec 12 2014
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MATHEMATICA
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Table[(n + 1) (n^3 + 15 n^2 + 74 n + 132) / 12, {n, 0, 50}] (* or *) CoefficientList[Series[(11 - 18 x + 12 x^2 - 3 x^3) / (1 - x)^5, {x, 0, 50}], x] (* Vincenzo Librandi, Dec 12 2014 *)
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PROG
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(Maxima) A217947(n):=(n+1)*(n^3+15*n^2+74*n+132)/12$
(Magma) [(n+1)*(n^3+15*n^2+74*n+132)/12: n in [0..50]] /* or */ I:=[11, 37, 87, 172, 305]; [n le 5 select I[n] else 5*Self(n-1)-10*Self(n-2)+10*Self(n-3)-5*Self(n-4)+Self(n-5): n in [1..50]] ; // Vincenzo Librandi, Dec 12 2014
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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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