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A211386
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Expansion of 1/((1-2*x)^5*(1-x)).
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3
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1, 11, 71, 351, 1471, 5503, 18943, 61183, 187903, 553983, 1579007, 4374527, 11829247, 31326207, 81461247, 208470015, 525991935, 1310457855, 3228041215, 7870611455, 19012780031, 45541752831, 108246597631, 255466668031, 598980165631, 1395931480063, 3235049897983
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OFFSET
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0,2
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COMMENTS
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Occurs in the enumerations of inflations of code words babxxxdc [Albert et al. Sec 5.5.1]
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LINKS
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FORMULA
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a(n) = 2^n*(24+18*n+23*n^2+6*n^3+n^4)/12-1.
a(0)=1, a(1)=11, a(2)=71, a(3)=351, a(4)=1471, a(5)=5503, a(n)=11*a(n-1)- 50*a(n-2)+ 120*a(n-3)-160*a(n-4)+112*a(n-5)-32*a(n-6). - Harvey P. Dale, Mar 02 2015
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MATHEMATICA
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CoefficientList[Series[1/((1-2x)^5(1-x)), {x, 0, 30}], x] (* or *) LinearRecurrence[ {11, -50, 120, -160, 112, -32}, {1, 11, 71, 351, 1471, 5503}, 30] (* Harvey P. Dale, Mar 02 2015 *)
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PROG
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(PARI) Vec(1/((1-2*x)^5*(1-x))+ O(x^30)) \\ Michel Marcus, Feb 12 2015
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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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