Incorrect duplicate of A058307.

Terms

a(0) =0a(1) =1a(2) =3a(3) =13a(4) =68a(5) =420a(6) =3015a(7) =24541a(8) =223884a(9) =2263381a(10) =25121075a(11) =303716281a(12) =3973432728a(13) =55931774473a(14) =842950049823