Base 9 digital convolution sequence.

Terms

a(0) =1a(1) =1a(2) =2a(3) =6a(4) =24a(5) =120a(6) =720a(7) =5040a(8) =40320a(9) =5040a(10) =45360a(11) =95760a(12) =332640a(13) =1426320a(14) =7464240a(15) =46211760a(16) =330946560a(17) =2693784240a(18) =661893120a(19) =6049461600a(20) =13422709440a(21) =52367051520a(22) =236313624960