m | n, n | m ⊦ m = n
⊦ gcd(m, gcd(n, n0)) | gcd(gcd(m, n), n0) ∧ gcd(gcd(m, n), n0) | gcd(m, gcd(n, n0)), gcd(m, gcd(n, n0)) = gcd(gcd(m, n), n0)
Used terms: gcd(m, gcd(n, n0)), gcd(gcd(m, n), n0)