E.g.f.: Product_{n>=1} cosh(x^n).A229263E.g.f.: Product_{n>=1} cosh(x^n).Terms a(0) =1a(1) =1a(2) =13a(3) =541a(4) =32761a(5) =3782521a(6) =570649861a(7) =126354119893External referencesoeis: A229263