a(n) = n!*LaguerreL(n, -4*n).A277418a(n) = n!*LaguerreL(n, -4*n).Terms a(0) =1a(1) =5a(2) =98a(3) =3246a(4) =151064a(5) =9052120a(6) =663449040a(7) =57490690544External referencesoeis: A277418