Bessel polynomial y_n(4).A065919Bessel polynomial y_n(4).Terms a(0) =1a(1) =5a(2) =61a(3) =1225a(4) =34361a(5) =1238221a(6) =54516085a(7) =2836074641a(8) =170218994545External referencesoeis: A065919