Expansion of e.g.f. log(1 + (exp(2*x) - 1)/2)^2 / 2.

Terms

a(0) =0a(1) =0a(2) =1a(3) =3a(4) =3a(5) =-10a(6) =-30a(7) =112a(8) =588a(9) =-2448a(10) =-18960a(11) =87296a(12) =911328a(13) =-4599296a(14) =-61152000a(15) =335523840a(16) =5464904448a(17) =-32363874304a(18) =-627708979200