a(n) = (n+1)*A001003(n).

Terms

a(0) =1a(1) =2a(2) =9a(3) =44a(4) =225a(5) =1182a(6) =6321a(7) =34232a(8) =187137a(9) =1030490a(10) =5707449a(11) =31760676a(12) =177435297a(13) =994551222a(14) =5590402785a(15) =31500824304a(16) =177880832001