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A188669
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a(n) = ceiling(binomial(2*n-1,n-1)/n).
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1
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1, 2, 4, 9, 26, 77, 246, 805, 2702, 9238, 32066, 112674, 400024, 1432736, 5170584, 18783763, 68635478, 252087092, 930138522, 3446163221, 12815663678, 47820430994, 178987624514, 671825076732, 2528212128756, 9536894864387, 36054433808299, 136583760727865, 518401146543812, 1971076359414358, 7506908923471954, 28634752202227978
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OFFSET
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1,2
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COMMENTS
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A useful lower bound when studying certain problems involving compositions.
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LINKS
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MATHEMATICA
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Table[Ceiling[Binomial[2 n - 1, n - 1]/n], {n, 35}] (* Harvey P. Dale, Apr. 09 2011 *)
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PROG
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(Magma) [Ceiling(Binomial(2*n-1, n-1)/n): n in [1..60]]; // Vincenzo Librandi, Sep 07 2016
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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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