Expansion of exp(tan(x)/cosh(x)).

Terms

a(0) =1a(1) =1a(2) =1a(3) =0a(4) =-3a(5) =12a(6) =117a(7) =336a(8) =-903a(9) =-2096a(10) =111529a(11) =1043328a(12) =687093a(13) =-29488704a(14) =320199453a(15) =8894706432a(16) =44530596081a(17) =-389860902656a(18) =254346923089