Expansion of e.g.f. log(sech(x) + arcsin(x)).

Terms

a(0) =0a(1) =1a(2) =-2a(3) =6a(4) =-20a(5) =128a(6) =-920a(7) =7784a(8) =-75616a(9) =863168a(10) =-10897792a(11) =153777536a(12) =-2374754560a(13) =40156766336a(14) =-733521418240