Theorem uzind4i 9825

Description: Induction on the upper integers that start at 𝑀. The first four give us the substitution instances we need, and the last two are the basis and the induction step. This is a stronger version of uzind4 9821 assuming that 𝜓 holds unconditionally. Notice that 𝑁 ∈ (ℤ_≥‘𝑀) implies that the lower bound 𝑀 is an integer (𝑀 ∈ ℤ, see eluzel2 9759). (Contributed by NM, 4-Sep-2005.) (Revised by AV, 13-Jul-2022.)

Hypotheses

Ref	Expression
uzind4i.1	⊢ (𝑗 = 𝑀 → (𝜑 ↔ 𝜓))
uzind4i.2	⊢ (𝑗 = 𝑘 → (𝜑 ↔ 𝜒))
uzind4i.3	⊢ (𝑗 = (𝑘 + 1) → (𝜑 ↔ 𝜃))
uzind4i.4	⊢ (𝑗 = 𝑁 → (𝜑 ↔ 𝜏))
uzind4i.5	⊢ 𝜓
uzind4i.6	⊢ (𝑘 ∈ (ℤ≥‘𝑀) → (𝜒 → 𝜃))

Assertion

Ref	Expression
uzind4i	⊢ (𝑁 ∈ (ℤ≥‘𝑀) → 𝜏)

Distinct variable groups:   𝑗,𝑁   𝜓,𝑗   𝜒,𝑗   𝜃,𝑗   𝜏,𝑗   𝜑,𝑘   𝑗,𝑘,𝑀

Allowed substitution hints:   𝜑(𝑗)   𝜓(𝑘)   𝜒(𝑘)   𝜃(𝑘)   𝜏(𝑘)   𝑁(𝑘)

Proof of Theorem uzind4i

Step	Hyp	Ref	Expression
1		uzind4i.1	. 2 ⊢ (𝑗 = 𝑀 → (𝜑 ↔ 𝜓))
2		uzind4i.2	. 2 ⊢ (𝑗 = 𝑘 → (𝜑 ↔ 𝜒))
3		uzind4i.3	. 2 ⊢ (𝑗 = (𝑘 + 1) → (𝜑 ↔ 𝜃))
4		uzind4i.4	. 2 ⊢ (𝑗 = 𝑁 → (𝜑 ↔ 𝜏))
5		uzind4i.5	. . 3 ⊢ 𝜓
6	5	a1i 9	. 2 ⊢ (𝑀 ∈ ℤ → 𝜓)
7		uzind4i.6	. 2 ⊢ (𝑘 ∈ (ℤ≥‘𝑀) → (𝜒 → 𝜃))
8	1, 2, 3, 4, 6, 7	uzind4 9821	1 ⊢ (𝑁 ∈ (ℤ≥‘𝑀) → 𝜏)

Syntax hints:   → wi 4   ↔ wb 105   = wceq 1397   ∈ wcel 2202  ‘cfv 5326  (class class class)co 6017  1c1 8032   + caddc 8034  ℤcz 9478  ℤ_≥cuz 9754

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 619  ax-in2 620  ax-io 716  ax-5 1495  ax-7 1496  ax-gen 1497  ax-ie1 1541  ax-ie2 1542  ax-8 1552  ax-10 1553  ax-11 1554  ax-i12 1555  ax-bndl 1557  ax-4 1558  ax-17 1574  ax-i9 1578  ax-ial 1582  ax-i5r 1583  ax-13 2204  ax-14 2205  ax-ext 2213  ax-sep 4207  ax-pow 4264  ax-pr 4299  ax-un 4530  ax-setind 4635  ax-cnex 8122  ax-resscn 8123  ax-1cn 8124  ax-1re 8125  ax-icn 8126  ax-addcl 8127  ax-addrcl 8128  ax-mulcl 8129  ax-addcom 8131  ax-addass 8133  ax-distr 8135  ax-i2m1 8136  ax-0lt1 8137  ax-0id 8139  ax-rnegex 8140  ax-cnre 8142  ax-pre-ltirr 8143  ax-pre-ltwlin 8144  ax-pre-lttrn 8145  ax-pre-ltadd 8147

This theorem depends on definitions:  df-bi 117  df-3or 1005  df-3an 1006  df-tru 1400  df-fal 1403  df-nf 1509  df-sb 1811  df-eu 2082  df-mo 2083  df-clab 2218  df-cleq 2224  df-clel 2227  df-nfc 2363  df-ne 2403  df-nel 2498  df-ral 2515  df-rex 2516  df-reu 2517  df-rab 2519  df-v 2804  df-sbc 3032  df-dif 3202  df-un 3204  df-in 3206  df-ss 3213  df-pw 3654  df-sn 3675  df-pr 3676  df-op 3678  df-uni 3894  df-int 3929  df-br 4089  df-opab 4151  df-mpt 4152  df-id 4390  df-xp 4731  df-rel 4732  df-cnv 4733  df-co 4734  df-dm 4735  df-rn 4736  df-res 4737  df-ima 4738  df-iota 5286  df-fun 5328  df-fn 5329  df-f 5330  df-fv 5334  df-riota 5970  df-ov 6020  df-oprab 6021  df-mpo 6022  df-pnf 8215  df-mnf 8216  df-xr 8217  df-ltxr 8218  df-le 8219  df-sub 8351  df-neg 8352  df-inn 9143  df-n0 9402  df-z 9479  df-uz 9755

This theorem is referenced by:  rebtwn2zlemshrink  10512  seqfveq2g  10738  seqhomog  10791  2expltfac  13011