Duplicate of A056899.

Terms

a(0) =2a(1) =3a(2) =11a(3) =83a(4) =227a(5) =443a(6) =1091a(7) =1523a(8) =2027a(9) =3251a(10) =6563a(11) =9803a(12) =11027a(13) =12323a(14) =13691