Duplicate of A033170.

Terms

a(0) =1a(1) =2a(2) =3a(3) =4a(4) =5a(5) =68a(6) =122a(7) =246a(8) =397a(9) =425a(10) =513a(11) =625a(12) =696a(13) =970a(14) =1062a(15) =1167a(16) =1215a(17) =1244a(18) =1251