a(n) = n! * Laguerre(n,-7).

Terms

a(0) =1a(1) =8a(2) =79a(3) =916a(4) =12113a(5) =179152a(6) =2921911a(7) =51988748a(8) =1000578817a(9) =20686611736a(10) =456805020959