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%I #3 Jun 24 2012 10:43:58
%S 1,3,9,34,61,261,709,1324,4937,15040,28561,107262,248341,522445,
%T 1972363,7591936,8835345,26421129,145475533,183752250,701184621,
%U 2234736295,2996725227,15105451596,32483720761,77618520551,217809217211,625456400842,1638545943301
%N a(n) = 1 + n + n*{n/2} + n*{n/2}*{n/3} + n*{n/2}*{n/3}*{n/4} +... where {x} = [x+1/2] = round(x).
%e a(2) = 1 + 2 + 2*1 + 2*1*1 + 2*1*1*1 = 9
%e a(3) = 1 + 3 + 3*2 + 3*2*1 + 3*2*1*1 + 3*2*1*1*1 + 3*2*1*1*1*1 = 34.
%o (PARI) {a(n)=1+sum(m=1, 2*n, prod(k=1, m, round(n/k)))}
%o for(n=0, 60, print1(a(n), ", "))
%Y Cf. A075885.
%K nonn
%O 0,2
%A _Paul D. Hanna_, Jun 24 2012
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