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%I #18 Sep 10 2017 05:25:04
%S 0,2,5,12,27,58,121,248,503,1014,2037,4084,8179,16370,32753,65520,
%T 131055,262126,524269,1048556,2097131,4194282,8388585,16777192,
%U 33554407,67108838,134217701,268435428,536870883,1073741794,2147483617
%N a(n) = ceiling(n^(1/n))^n - n.
%F a(1)=0; a(n) = 2^n - n for n > 1. - _Benoit Cloitre_, Nov 28 2002
%p a:=n->sum(binomial(n,k)+binomial(k,n), k=2..n): seq(a(n), n=1..31); # _Zerinvary Lajos_, Apr 29 2007
%t Table[Ceiling[n^(1/n)]^n-n, {n, 1, 30}]
%Y Same as A000325 except for the first term.
%K nonn
%O 1,2
%A _Joseph L. Pe_, Nov 25 2002