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%I #12 May 08 2018 04:49:41
%S 1,2,3,6,9,18,30,56,101,186,339,630,1167,2182,4092,7710,14561,27594,
%T 52425,99862,190647,364722,699045,1342176,2581107,4971024,9586975,
%U 18512790,35791386,69273666,134217720,260301046,505290269,981706808
%N a(n) = Sum_{k=0..n} floor(binomial(n,k)/(k+1)).
%C Row sums of A011847.
%H Robert Israel, <a href="/A095718/b095718.txt">Table of n, a(n) for n = 1..3329</a>
%F a(n) = Sum_{k=0..n} floor(binomial(n,k)/(k+1)).
%F From _Robert Israel_, May 07 2018: (Start)
%F (2^(n+1)-1)/(n+1) >= a(n) >= (2^(n+1)-1)/(n+1) - n.
%F It appears that a(n) = (2^(n+1)-2)/(n+1) if n+1 is prime. (End)
%p a:=n->add(floor(combinat[numbcomb](n,k)/(k+1)),k=0..n);
%o (PARI) a(n) = sum(k=0, n, binomial(n,k)\(k+1)); \\ _Michel Marcus_, May 08 2018
%Y Cf. A011847, A101687.
%K nonn
%O 1,2
%A _Mike Zabrocki_, Jul 08 2004
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