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A095718
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a(n) = Sum_{k=0..n} floor(binomial(n,k)/(k+1)).
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3
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1, 2, 3, 6, 9, 18, 30, 56, 101, 186, 339, 630, 1167, 2182, 4092, 7710, 14561, 27594, 52425, 99862, 190647, 364722, 699045, 1342176, 2581107, 4971024, 9586975, 18512790, 35791386, 69273666, 134217720, 260301046, 505290269, 981706808
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OFFSET
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1,2
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COMMENTS
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LINKS
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FORMULA
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a(n) = Sum_{k=0..n} floor(binomial(n,k)/(k+1)).
(2^(n+1)-1)/(n+1) >= a(n) >= (2^(n+1)-1)/(n+1) - n.
It appears that a(n) = (2^(n+1)-2)/(n+1) if n+1 is prime. (End)
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MAPLE
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a:=n->add(floor(combinat[numbcomb](n, k)/(k+1)), k=0..n);
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PROG
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(PARI) a(n) = sum(k=0, n, binomial(n, k)\(k+1)); \\ Michel Marcus, May 08 2018
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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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