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

Terms

a(0) =1a(1) =1a(2) =3a(3) =11a(4) =47a(5) =239a(6) =1439a(7) =10079a(8) =80639a(9) =725759a(10) =7257599a(11) =79833599a(12) =958003199a(13) =12454041599a(14) =174356582399