English
For all n, the Dickson polynomial with k = 1 and a = 1 equals Chebyshev C evaluated at n: D_1,1(n) = Chebyshev.C_R(n).
Русский
Для всех n полином Диксона при k = 1 и a = 1 равен Chebyshev C(n).
LaTeX
$$dickson\, 1\, (1)\, n = Chebyshev.C\, R\, n$$
Lean4
theorem dickson_one_one_eq_chebyshev_C : ∀ n, dickson 1 (1 : R) n = Chebyshev.C R n
| 0 => by
simp only [dickson_zero]
norm_num
| 1 => by rw [dickson_one, Nat.cast_one, Chebyshev.C_one]
| n + 2 =>
by
rw [dickson_add_two, C_1, Nat.cast_add, Nat.cast_two, Chebyshev.C_add_two, dickson_one_one_eq_chebyshev_C (n + 1),
dickson_one_one_eq_chebyshev_C n]
push_cast
ring