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%I #5 Jun 16 2016 23:24:42
%S 1,11,83,741,8169,106107,1592235,27062325,514246545,10798366635,
%T 248374594755,6209158112325,167651197407225,4861802228946075,
%U 150717766502187675,4973638859450709525,174078640829054894625
%N The second column of the ED3 array A167572.
%H G. C. Greubel, <a href="/A167577/b167577.txt">Table of n, a(n) for n = 1..150</a>
%F a(n) = (1/2)*(-1)^n*(2*n-5)!!*((4*n^2-6*n-2)+(16*n^3-24*n^2-4*n+6)*sum((-1)^(k+n)/ (2*k+1), k=0..n-1)).
%t Table[(1/2)*(-1)^n*(2*n - 5)!!*((4*n^2 - 6*n - 2) + (16*n^3 - 24*n^2 - 4*n + 6)*Sum[(-1)^(k + n)/(2*k + 1), {k, 0, n - 1}]), {n, 1,50}] (* _G. C. Greubel_, Jun 16 2016 *)
%Y Equals the second column of the ED3 array A167572.
%Y Other columns are A167576 and A167578.
%Y Cf. A007509 and A025547 (the sum((-1)^(k+n)/(2*k+1), k=0..n-1) factor).
%K easy,nonn
%O 1,2
%A _Johannes W. Meijer_, Nov 10 2009
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