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%I #3 Mar 30 2012 16:49:19
%S -1,0,8,56,304,1496,6992,31664,140384,613016,2646544,11325200,
%T 48122528,203306736,854829344,3579783776,14939605184,62162742296,
%U 257985394064,1068242117456,4414349525024,18208784215376,74988168359264,308369069291936
%N 2n*binomial(2n,n) - 4^n.
%C Known to be >= 0 for n>0.
%D Hojoo Lee, Posting to Number Theory List, Feb 18 2002.
%K sign
%O 0,3
%A _N. J. A. Sloane_, Mar 23 2002