a(1) = 3; a(2) = 11; to get a(n), n >= 3, convert a(n-1) from base 3 to base 2.

A008561

a(1) = 3; a(2) = 11; to get a(n), n >= 3, convert a(n-1) from base 3 to base 2.

Terms

    a(0) =3a(1) =11a(2) =100a(3) =1001a(4) =11100a(5) =1110101a(6) =10000100111

External references