E.g.f. exp(tanh(x)).

Terms

a(0) =1a(1) =1a(2) =1a(3) =-1a(4) =-7a(5) =-3a(6) =97a(7) =275a(8) =-2063a(9) =-15015a(10) =53409a(11) =968167a(12) =-752343a(13) =-77000363a(14) =-166831871a(15) =7433044411a(16) =43685848289a(17) =-843598411471