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

Terms

a(0) =1a(1) =-1a(2) =0a(3) =2a(4) =-8a(5) =24a(6) =-56a(7) =104a(8) =64a(9) =-1792a(10) =12672a(11) =-68608a(12) =309376a(13) =-1203840a(14) =2917888a(15) =5570816a(16) =-163782656a(17) =1636425728a(18) =-12716052480a(19) =86205304832a(20) =-495644917760