a(n) = prime(n)!/(n+1)!.A178614a(n) = prime(n)!/(n+1)!.Terms a(0) =1a(1) =1a(2) =5a(3) =42a(4) =55440a(5) =1235520a(6) =8821612800a(7) =335221286400External referencesoeis: A178614