a(1) =9, a(n) = smallest multiple of a(n-1) (not equal to 10^k*a(n-1)) obtained by inserting digits anywhere in a(n-1).

A080494

a(1) =9, a(n) = smallest multiple of a(n-1) (not equal to 10^k*a(n-1)) obtained by inserting digits anywhere in a(n-1).

Terms

    a(0) =9a(1) =99a(2) =9009a(3) =909909a(4) =908999091

External references