a(n) is formed by concatenating a(n-2) and a(n-1), with a(0) = 1, a(1) = 2.

A008352

a(n) is formed by concatenating a(n-2) and a(n-1), with a(0) = 1, a(1) = 2.

Terms

    a(0) =1a(1) =2a(2) =12a(3) =212a(4) =12212a(5) =21212212

External references