Metamath Proof Explorer


Theorem mod2xi

Description: Double exponents in a power mod calculation. (Contributed by Mario Carneiro, 21-Feb-2014)

Ref Expression
Hypotheses modxai.1 𝑁 ∈ ℕ
modxai.2 𝐴 ∈ ℕ
modxai.3 𝐵 ∈ ℕ0
modxai.4 𝐷 ∈ ℤ
modxai.5 𝐾 ∈ ℕ0
modxai.6 𝑀 ∈ ℕ0
mod2xi.9 ( ( 𝐴𝐵 ) mod 𝑁 ) = ( 𝐾 mod 𝑁 )
mod2xi.7 ( 2 · 𝐵 ) = 𝐸
mod2xi.8 ( ( 𝐷 · 𝑁 ) + 𝑀 ) = ( 𝐾 · 𝐾 )
Assertion mod2xi ( ( 𝐴𝐸 ) mod 𝑁 ) = ( 𝑀 mod 𝑁 )

Proof

Step Hyp Ref Expression
1 modxai.1 𝑁 ∈ ℕ
2 modxai.2 𝐴 ∈ ℕ
3 modxai.3 𝐵 ∈ ℕ0
4 modxai.4 𝐷 ∈ ℤ
5 modxai.5 𝐾 ∈ ℕ0
6 modxai.6 𝑀 ∈ ℕ0
7 mod2xi.9 ( ( 𝐴𝐵 ) mod 𝑁 ) = ( 𝐾 mod 𝑁 )
8 mod2xi.7 ( 2 · 𝐵 ) = 𝐸
9 mod2xi.8 ( ( 𝐷 · 𝑁 ) + 𝑀 ) = ( 𝐾 · 𝐾 )
10 3 nn0cni 𝐵 ∈ ℂ
11 10 2timesi ( 2 · 𝐵 ) = ( 𝐵 + 𝐵 )
12 11 8 eqtr3i ( 𝐵 + 𝐵 ) = 𝐸
13 1 2 3 4 5 6 3 5 7 7 12 9 modxai ( ( 𝐴𝐸 ) mod 𝑁 ) = ( 𝑀 mod 𝑁 )