a(n) = 6*n! + 1.

Terms

a(0) =7a(1) =7a(2) =13a(3) =37a(4) =145a(5) =721a(6) =4321a(7) =30241a(8) =241921a(9) =2177281a(10) =21772801a(11) =239500801a(12) =2874009601a(13) =37362124801a(14) =523069747201