%I #8 Mar 30 2012 18:41:11
%S 1,-1,0,3,-6,30,0,-630,2520,-22680,0,1247400,-7484400,97297200,0,
%T -10216206000,81729648000,-1389404016000,0,237588086736000,
%U -2375880867360000,49893498214560000,0,-12623055048283680000
%N Expand cos x / exp x and invert nonzero coefficients.
%F a(4n+2) = 0, a(n) = (-1)^[n == 1, 4, 7 mod 8] * n!/2^floor(n/2). - _Ralf Stephan_, Mar 06 2004
%Y Absolute values are essentially the same as A046981, where zeros are replaced by ones.
%Y Cf. A052277, A007019, A046979, A007415, A009775, A092820.
%K sign
%O 0,4
%A _N. J. A. Sloane_.