a(n+1) = n*a(n) + a(n-1) with a(0)=0, a(1)=1.

Terms

a(0) =0a(1) =1a(2) =1a(3) =3a(4) =10a(5) =43a(6) =225a(7) =1393a(8) =9976a(9) =81201a(10) =740785a(11) =7489051a(12) =83120346a(13) =1004933203a(14) =13147251985a(15) =185066460993