English
If i ≤ j ≤ 2n and xn(a1, i) ≡ xn(a1, j) (mod xn(a1, n)) with a nondegeneracy condition, then i = j.
Русский
Если i ≤ j ≤ 2n и xn(a1,i) ≡ xn(a1,j) (mod xn(a1,n)) при условии отсутствия вырождения, то i = j.
LaTeX
$$$$ i \\le j \\le 2n, \\ xn(a1,i) \\equiv xn(a1,j) \\pmod{ xn(a1,n) } \\Rightarrow i = j $$$$
Lean4
theorem pow_add_mul_totient_mod_eq {x k l n : ℕ} (hn : 1 < n) (h : x.Coprime n) :
(x ^ (k + l * φ n)) % n = (x ^ k) % n := by
induction l with
| zero => simp
| succ l ih => rw [add_mul, one_mul, ← add_assoc, pow_add_totient_mod_eq hn h, ih]