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A193045
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Coefficient of x in the reduction by x^2->x+1 of the polynomial p(n,x) defined at Comments.
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1
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0, 1, 1, 3, 8, 21, 49, 105, 210, 399, 729, 1293, 2242, 3821, 6427, 10703, 17690, 29073, 47579, 77621, 126340, 205291, 333171, 540233, 875428, 1417961, 2295989, 3716875, 6016140, 9736669, 15756869, 25498033, 41259862, 66763351, 108029197
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OFFSET
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0,4
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COMMENTS
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The titular polynomials are defined recursively: p(n,x)=x*p(n-1,x)+n(-1+n^2)/6, with p(0,x)=1. For an introduction to reductions of polynomials by substitutions such as x^2->x+1, see A192232 and A192744.
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LINKS
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Table of n, a(n) for n=0..34.
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FORMULA
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a(n)=5*a(n-1)-9*a(n-2)+6*a(n-3)+a(n-4)-3*a(n-5)+a(n-6).
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MATHEMATICA
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(See A193044.)
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CROSSREFS
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Cf. A192232, A192744, A192951, A193044.
Sequence in context: A007773 A071078 A179903 * A096770 A007835 A152086
Adjacent sequences: A193042 A193043 A193044 * A193046 A193047 A193048
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KEYWORD
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nonn
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AUTHOR
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Clark Kimberling, Jul 15 2011
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STATUS
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approved
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