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A169959
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a(n) = binomial(10*n, n).
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3
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1, 10, 190, 4060, 91390, 2118760, 50063860, 1198774720, 28987537150, 706252528630, 17310309456440, 426342151127100, 10542859559688820, 261594860525768000, 6509613950241656640, 162392216278033616560, 4059949873964357469950, 101696990867999141755140
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OFFSET
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0,2
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LINKS
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FORMULA
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a(n) = C(10*n-1, n-1)*C(100*n^2, 2)/(3*n*C(10*n+1, 3)), n > 0. - Gary Detlefs, Jan 02 2014
The o.g.f. A(x) is algebraic: (1 - A(x))*(1 + 9*A(x))^9 + (10^10)*x*A(x)^10 = 0.
Sum_{n >= 1} a(n)*( x*(9*x + 10)^9/(10^10*(1 + x)^10) )^n = x. (End)
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PROG
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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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