18305618100domain: NAppears in sequencesa(n) = (3^n-1)*(n+1)/4.at n=19A261064Expansion of e.g.f. x*exp(x)*cosh(x)*sinh(x).at n=21A360035Expansion of e.g.f. x*exp(x)*(sinh(x))^2.at n=21A360036