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A093969
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a(n) = n*Pell(n-2).
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2
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0, 1, 0, 3, 8, 25, 72, 203, 560, 1521, 4080, 10835, 28536, 74633, 194040, 501915, 1292512, 3315425, 8474976, 21597091, 54884200, 139127289, 351877416, 888121195, 2237336592, 5626467025, 14126832720, 35416929267, 88670846936
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OFFSET
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0,4
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COMMENTS
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The signed version (-1)^(n+1)*n*Pell(n-2) is the second inverse binomial transform of A093967.
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LINKS
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FORMULA
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G.f.: x(1-4x+5x^2)/(1-2x-x^2)^2;
a(n) = n*(1 + sqrt(2))^n*(3*sqrt(2)/4 - 1) - n*(1 - sqrt(2))^n*(3*sqrt(2)/4 + 1).
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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STATUS
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approved
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