LB numbers: positive integers of the form m = a*10^k+b (with a > 0 and b < 10^k) satisfying two properties: 1) the set of prime factors of m is the union of the sets of prime factors of a and b; and 2) A001222(m) = A001222(a) + A001222(b).

A267856

LB numbers: positive integers of the form m = a*10^k+b (with a > 0 and b < 10^k) satisfying two properties: 1) the set of prime factors of m is the union of the sets of prime factors of a and b; and 2) A001222(m) = A001222(a) + A001222(b).