a(n) = 7 * n!.

Terms

a(0) =7a(1) =14a(2) =42a(3) =168a(4) =840a(5) =5040a(6) =35280a(7) =282240a(8) =2540160a(9) =25401600a(10) =279417600a(11) =3353011200a(12) =43589145600a(13) =610248038400