%I A104042
%S A104042 4,8,28,8,248,16,508,136,584,496,16376,16,131056,174752,18724,2056,1048568,
%T A104042 1168,4194296,20336,684784,1945184,67108856,3856,536870896,715827872,306783376,
%U A104042 19746976,17179869152,3198784,8589934588,134744072,426829048,91625968976
%V A104042 4,-8,28,-8,248,-16,508,-136,584,-496,16376,-16,131056,-174752,18724,-2056,
               1048568,
%W A104042 -1168,4194296,-20336,684784,-1945184,67108856,-3856,536870896,-715827872,
               306783376,
%X A104042 -19746976,17179869152,-3198784,8589934588,-134744072,426829048,-91625968976
%N A104042 Numerators of coefficients in expansion of x^-2*(1-exp(-2*x))^2.
%C A104042 Suggested by Bill Gosper's remarkable identity (in a posting to math-fun 
               list, Apr 14 2005): Product_{ n >= 0 } tanh(2^n x)^(1/2^n) = (1-exp(-2*x))^2.
%t A104042 Numerator[ CoefficientList[ Series[x^-2*(1 - E^(-2x))^2, {x, 0, 33}], 
               x]] (from Robert G. Wilson v (rgwv(AT)rgwv.com), Apr 20 2005)
%Y A104042 Cf. A104097, A104007, A104042.
%Y A104042 Sequence in context: A036720 A110132 A099513 this_sequence A117864 A020138 
               A090083
%Y A104042 Adjacent sequences: A104039 A104040 A104041 this_sequence A104043 A104044 
               A104045
%K A104042 sign,frac
%O A104042 0,1
%A A104042 N. J. A. Sloane (njas(AT)research.att.com), Apr 18 2005