Metamath Proof Explorer


Theorem fzindd

Description: Induction on the integers from M to N inclusive, a deduction version. (Contributed by metakunt, 12-May-2024)

Ref Expression
Hypotheses fzindd.1 ( 𝑥 = 𝑀 → ( 𝜓𝜒 ) )
fzindd.2 ( 𝑥 = 𝑦 → ( 𝜓𝜃 ) )
fzindd.3 ( 𝑥 = ( 𝑦 + 1 ) → ( 𝜓𝜏 ) )
fzindd.4 ( 𝑥 = 𝐴 → ( 𝜓𝜂 ) )
fzindd.5 ( 𝜑𝜒 )
fzindd.6 ( ( 𝜑 ∧ ( 𝑦 ∈ ℤ ∧ 𝑀𝑦𝑦 < 𝑁 ) ∧ 𝜃 ) → 𝜏 )
fzindd.7 ( 𝜑𝑀 ∈ ℤ )
fzindd.8 ( 𝜑𝑁 ∈ ℤ )
fzindd.9 ( 𝜑𝑀𝑁 )
Assertion fzindd ( ( 𝜑 ∧ ( 𝐴 ∈ ℤ ∧ 𝑀𝐴𝐴𝑁 ) ) → 𝜂 )

Proof

Step Hyp Ref Expression
1 fzindd.1 ( 𝑥 = 𝑀 → ( 𝜓𝜒 ) )
2 fzindd.2 ( 𝑥 = 𝑦 → ( 𝜓𝜃 ) )
3 fzindd.3 ( 𝑥 = ( 𝑦 + 1 ) → ( 𝜓𝜏 ) )
4 fzindd.4 ( 𝑥 = 𝐴 → ( 𝜓𝜂 ) )
5 fzindd.5 ( 𝜑𝜒 )
6 fzindd.6 ( ( 𝜑 ∧ ( 𝑦 ∈ ℤ ∧ 𝑀𝑦𝑦 < 𝑁 ) ∧ 𝜃 ) → 𝜏 )
7 fzindd.7 ( 𝜑𝑀 ∈ ℤ )
8 fzindd.8 ( 𝜑𝑁 ∈ ℤ )
9 fzindd.9 ( 𝜑𝑀𝑁 )
10 7 8 jca ( 𝜑 → ( 𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ ) )
11 1 imbi2d ( 𝑥 = 𝑀 → ( ( 𝜑𝜓 ) ↔ ( 𝜑𝜒 ) ) )
12 2 imbi2d ( 𝑥 = 𝑦 → ( ( 𝜑𝜓 ) ↔ ( 𝜑𝜃 ) ) )
13 3 imbi2d ( 𝑥 = ( 𝑦 + 1 ) → ( ( 𝜑𝜓 ) ↔ ( 𝜑𝜏 ) ) )
14 4 imbi2d ( 𝑥 = 𝐴 → ( ( 𝜑𝜓 ) ↔ ( 𝜑𝜂 ) ) )
15 5 a1i ( ( 𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ ∧ 𝑀𝑁 ) → ( 𝜑𝜒 ) )
16 6 3expa ( ( ( 𝜑 ∧ ( 𝑦 ∈ ℤ ∧ 𝑀𝑦𝑦 < 𝑁 ) ) ∧ 𝜃 ) → 𝜏 )
17 16 ex ( ( 𝜑 ∧ ( 𝑦 ∈ ℤ ∧ 𝑀𝑦𝑦 < 𝑁 ) ) → ( 𝜃𝜏 ) )
18 17 expcom ( ( 𝑦 ∈ ℤ ∧ 𝑀𝑦𝑦 < 𝑁 ) → ( 𝜑 → ( 𝜃𝜏 ) ) )
19 18 a2d ( ( 𝑦 ∈ ℤ ∧ 𝑀𝑦𝑦 < 𝑁 ) → ( ( 𝜑𝜃 ) → ( 𝜑𝜏 ) ) )
20 19 adantl ( ( ( 𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ ) ∧ ( 𝑦 ∈ ℤ ∧ 𝑀𝑦𝑦 < 𝑁 ) ) → ( ( 𝜑𝜃 ) → ( 𝜑𝜏 ) ) )
21 11 12 13 14 15 20 fzind ( ( ( 𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ ) ∧ ( 𝐴 ∈ ℤ ∧ 𝑀𝐴𝐴𝑁 ) ) → ( 𝜑𝜂 ) )
22 10 21 sylan ( ( 𝜑 ∧ ( 𝐴 ∈ ℤ ∧ 𝑀𝐴𝐴𝑁 ) ) → ( 𝜑𝜂 ) )
23 22 imp ( ( ( 𝜑 ∧ ( 𝐴 ∈ ℤ ∧ 𝑀𝐴𝐴𝑁 ) ) ∧ 𝜑 ) → 𝜂 )
24 23 anabss1 ( ( 𝜑 ∧ ( 𝐴 ∈ ℤ ∧ 𝑀𝐴𝐴𝑁 ) ) → 𝜂 )