Theorem sucinc 6618

Description: Successor is increasing. (Contributed by Jim Kingdon, 25-Jun-2019.)

Hypothesis

Ref	Expression
sucinc.1	⊢ 𝐹 = (𝑧 ∈ V ↦ suc 𝑧)

Assertion

Ref	Expression
sucinc	⊢ ∀𝑥 𝑥 ⊆ (𝐹‘𝑥)

Distinct variable group:   𝑥,𝑧

Allowed substitution hints:   𝐹(𝑥,𝑧)

Proof of Theorem sucinc

Step	Hyp	Ref	Expression
1		sssucid 4514	. . 3 ⊢ 𝑥 ⊆ suc 𝑥
2		vex 2804	. . . 4 ⊢ 𝑥 ∈ V
3	2	sucex 4599	. . . 4 ⊢ suc 𝑥 ∈ V
4		suceq 4501	. . . . 5 ⊢ (𝑧 = 𝑥 → suc 𝑧 = suc 𝑥)
5		sucinc.1	. . . . 5 ⊢ 𝐹 = (𝑧 ∈ V ↦ suc 𝑧)
6	4, 5	fvmptg 5725	. . . 4 ⊢ ((𝑥 ∈ V ∧ suc 𝑥 ∈ V) → (𝐹‘𝑥) = suc 𝑥)
7	2, 3, 6	mp2an 426	. . 3 ⊢ (𝐹‘𝑥) = suc 𝑥
8	1, 7	sseqtrri 3261	. 2 ⊢ 𝑥 ⊆ (𝐹‘𝑥)
9	8	ax-gen 1497	1 ⊢ ∀𝑥 𝑥 ⊆ (𝐹‘𝑥)

Syntax hints:  ∀wal 1395   = wceq 1397   ∈ wcel 2201  Vcvv 2801   ⊆ wss 3199   ↦ cmpt 4151  suc csuc 4464  ‘cfv 5328

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-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 2203  ax-14 2204  ax-ext 2212  ax-sep 4208  ax-pow 4266  ax-pr 4301  ax-un 4532

This theorem depends on definitions:  df-bi 117  df-3an 1006  df-tru 1400  df-nf 1509  df-sb 1810  df-eu 2081  df-mo 2082  df-clab 2217  df-cleq 2223  df-clel 2226  df-nfc 2362  df-ral 2514  df-rex 2515  df-v 2803  df-sbc 3031  df-un 3203  df-in 3205  df-ss 3212  df-pw 3655  df-sn 3676  df-pr 3677  df-op 3679  df-uni 3895  df-br 4090  df-opab 4152  df-mpt 4153  df-id 4392  df-suc 4470  df-xp 4733  df-rel 4734  df-cnv 4735  df-co 4736  df-dm 4737  df-iota 5288  df-fun 5330  df-fv 5336

This theorem is referenced by: (None)