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A108993
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a(n) = A108992(n)/(n+1). A(x) = 1/x*series_reversion(x/G108996(x)) where G108996(x) is g.f. of A108996.
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6
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1, 1, 3, 19, 205, 3276, 70852, 1953715, 65904057, 2639266228, 122677374326, 6503266277223, 387708627582311, 25700183133977665, 1876381387159576676, 149695388098709302361, 12961535832843534300945
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OFFSET
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0,3
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COMMENTS
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A108992 is the second diagonal of triangle A108990, in which the g.f. of row n, R_n(x), satisfies: [x^k] R_{n+1}(x) = [x^k] (1 + x*R_n(x))^(n+1) for k=0..n+1.
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LINKS
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PROG
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(PARI) {a(n)=local(F=1+x*O(x^n)); for(m=1, n+1, F=(1+x*F)^m); polcoeff(F, n)/(n+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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