a(0)=a(1)=0; thereafter a(n) = A162973(n)/(n-1).

Terms

a(0) =0a(1) =0a(2) =1a(3) =1a(4) =4a(5) =16a(6) =85a(7) =533a(8) =3888a(9) =32268a(10) =300193a(11) =3093377a(12) =34970468a(13) =430293488a(14) =5724411845a(15) =81871668773