Expansion of e.g.f. cos(x)/exp(sinh(x)).

Terms

a(0) =1a(1) =-1a(2) =0a(3) =1a(4) =0a(5) =3a(6) =-24a(7) =61a(8) =-256a(9) =1383a(10) =-5632a(11) =28345a(12) =-156032a(13) =808299a(14) =-4761600a(15) =28955317a(16) =-178225152a(17) =1188919631a(18) =-8081772544a(19) =56978370417a(20) =-422364381184