Duplicate of A001112.

Terms

a(0) =1a(1) =1a(2) =3a(3) =4a(4) =11a(5) =136a(6) =283a(7) =419a(8) =1121a(9) =1540a(10) =38081a(11) =39621a(12) =117323a(13) =156944