a(n) = (1/n!)*A001565(n).

Terms

a(0) =2a(1) =11a(2) =32a(3) =71a(4) =134a(5) =227a(6) =356a(7) =527a(8) =746a(9) =1019a(10) =1352a(11) =1751a(12) =2222a(13) =2771a(14) =3404a(15) =4127a(16) =4946a(17) =5867a(18) =6896a(19) =8039a(20) =9302a(21) =10691a(22) =12212a(23) =13871a(24) =15674a(25) =17627a(26) =19736a(27) =22007a(28) =24446a(29) =27059