Expansion of log(1+sin(x))/cosh(x).

Terms

a(0) =0a(1) =1a(2) =-1a(3) =-2a(4) =4a(5) =20a(6) =-61a(7) =-296a(8) =1184a(9) =9680a(10) =-49201a(11) =-393120a(12) =2361844a(13) =26927680a(14) =-191422141a(15) =-2138039424a(16) =17147588384a(17) =250712561920