|
%I #2 Mar 30 2012 17:31:15
%S 12,13,21,22,25,27,28,29,32,42,43,50,52,54,62,64,66,70,72,73,76,81,82,
%T 85,87,90,91,92,96,99,102,103,106,112,117,120,122,123,126,129,131,132,
%U 135,140,142,144,147,152,154,155,158,159,162,169
%N Numbers n such that A105658(2n-1) != 2n-1 and A105658(2n) != n.
%F A105658(n) = Product_{i=1..n} i^i / denominator( sum_{j=1..n} j(j+1)/2 / product_{k=0..i-1} j!/k!) ).
%t f[n_] := f[n] = Product[i^i, {i, n}]/Denominator[Sum[j(j + 1)/2/(Product[j!/k!, {k, 0, j - 1}]), {j, n}]]; Select[ Range[125], f[2# - 1] != 2# - 1 && f[2# ] != # &]
%Y Cf. A105658, A105731, A105732, A105769.
%K nonn
%O 1,1
%A Jess E. Boling (tdbpeekitup(AT)yahoo.com) and _Robert G. Wilson v_, Apr 18 2005
|
