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%I #19 Mar 06 2020 09:52:32
%S 1,5,16,50,147,422,1210,3459,9878,28189,80425,229411,654311,1866003,
%T 5321194,15173321,43264523,123357771,351712022,1002758190,2858875748,
%U 8150529454,23236408366,66243882238,188849982251,538372895393,1534776215805,4375251800924
%N Integer part of Sum_{i=1..n} binomial(n,i) * (n/i)^i.
%H G. C. Greubel, <a href="/A007806/b007806.txt">Table of n, a(n) for n = 1..1000</a>
%p a:= n-> floor(add(binomial(n, i)*(n/i)^i, i = 1..n)):
%p seq(a(n), n=1..30);
%t Floor/@Table[Sum[Binomial[n,i](n/i)^i,{i,n}],{n,30}] (* _Harvey P. Dale_, May 08 2012 *)
%o (PARI) a(n) = sum(i=1, n, binomial(n,i)*(n/i)^i)\1; \\ _Michel Marcus_, Oct 30 2018
%o (Sage) [floor( sum(binomial(n,j)*(n/j)^j for j in (1..n)) ) for n in (1..30)] # _G. C. Greubel_, Mar 06 2020
%K nonn
%O 1,2
%A Joseph Lavinus Ganley [ ganley(AT)virginia.edu ]
%E Name corrected June 1995
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