a(1) = 1, a(2) = 2, a(n) = reverse concatenation of two previous terms.

A091789

a(1) = 1, a(2) = 2, a(n) = reverse concatenation of two previous terms.

Terms

    a(0) =1a(1) =2a(2) =21a(3) =122a(4) =22112a(5) =21122221

External references