Expansion of e.g.f. 1/(cosh(x) - tanh(x)).

Terms

a(0) =1a(1) =1a(2) =1a(3) =-2a(4) =-23a(5) =-104a(6) =-119a(7) =3088a(8) =37297a(9) =209536a(10) =-569039a(11) =-29795072a(12) =-376722983a(13) =-1715047424a(14) =35167499641