Expansion of log(1+tanh(tanh(x))).

Terms

a(0) =0a(1) =1a(2) =-1a(3) =-2a(4) =10a(5) =16a(6) =-232a(7) =-272a(8) =10064a(9) =7936a(10) =-720384a(11) =-353792a(12) =78009600a(13) =22368256a(14) =-11977120768a(15) =-1903757312a(17) =209865342976