The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

A083985

If k is a number with exactly two distinct decimal digits, say a and b, neither of which is 0 (i.e., a member of A101594), define the self-complement of k, SC(k), to be the number obtained by replacing a with b and vice versa. Then a(n) = gcd(A101594(n), SC(A101594(n))).