a(n) = A000111(2n) + A000111(2n+1).

A141458

a(n) = A000111(2n) + A000111(2n+1).

Terms

    a(0) =2a(1) =3a(2) =21a(3) =333a(4) =9321a(5) =404313a(6) =25071021a(7) =2103118293a(8) =229256855121

External references