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A187118
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Rows sums of triangle A187115.
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4
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1, 3, 12, 67, 512, 5143, 64988, 995334, 17948683, 372703529, 8759307844, 229843336284, 6660078541359, 211201170221925, 7274712426981184, 270441300892307916, 10791919593795653296, 460087687818627367809
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OFFSET
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2,2
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COMMENTS
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Definition of triangle: A187115(n,k) = [y^k] R_{n-1}(y+y^2) for k=2..n, n>2, where R_n(y) is the n-th row polynomial starting with R_2(y)=y^2.
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LINKS
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PROG
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(PARI) {a(n)=local(Rn=y^2); for(m=2, n, Rn=subst(truncate(Rn), y, y+y^2+O(y^m))); subst(truncate(Rn), y, 1)}
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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