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A179904
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a(n) = A056520(n)+1 for n>0, a(0)=1.
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5
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1, 3, 7, 16, 32, 57, 93, 142, 206, 287, 387, 508, 652, 821, 1017, 1242, 1498, 1787, 2111, 2472, 2872, 3313, 3797, 4326, 4902, 5527, 6203, 6932, 7716, 8557, 9457, 10418, 11442, 12531, 13687, 14912, 16208, 17577, 19021, 20542, 22142, 23823, 25587
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OFFSET
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0,2
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COMMENTS
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Original name: (1,3,5,7,9,..) = A005408 convolved with (1,0,2,3,4,..) = 1 followed by A087156.
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LINKS
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FORMULA
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G.f.: (1 + x)*(1 - 2*x + 3*x^2 - x^3)/(1 - x)^4.
a(n) = (1/6)*(2*n^3 + 3*n^2 + n + 12) for n>0, a(0)=1. (End)
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EXAMPLE
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a(3) = 16 = 1 + A056250(3) = (1 + 15).
a(4) = 32 = (9, 7, 5, 3, 1) dot (1, 0, 2, 3, 4) = (9 + 0 + 10 + 9 + 4).
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MATHEMATICA
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LinearRecurrence[{4, -6, 4, -1}, {1, 3, 7, 16, 32}, 50] (* Harvey P. Dale, Apr 25 2020 *)
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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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EXTENSIONS
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STATUS
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approved
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