Theorem sucinc2 6719

Description: Successor is increasing. (Contributed by Jim Kingdon, 14-Jul-2019.)

Hypothesis

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

Assertion

Ref	Expression
sucinc2	⊢ ((𝐵 ∈ On ∧ 𝐴 ∈ 𝐵) → (𝐹‘𝐴) ⊆ (𝐹‘𝐵))

Distinct variable groups:   𝑧,𝐴   𝑧,𝐵

Allowed substitution hint:   𝐹(𝑧)

Proof of Theorem sucinc2

Step	Hyp	Ref	Expression
1		eloni 4520	. . . . 5 ⊢ (𝐵 ∈ On → Ord 𝐵)
2		ordsucss 4651	. . . . 5 ⊢ (Ord 𝐵 → (𝐴 ∈ 𝐵 → suc 𝐴 ⊆ 𝐵))
3	1, 2	syl 14	. . . 4 ⊢ (𝐵 ∈ On → (𝐴 ∈ 𝐵 → suc 𝐴 ⊆ 𝐵))
4	3	imp 124	. . 3 ⊢ ((𝐵 ∈ On ∧ 𝐴 ∈ 𝐵) → suc 𝐴 ⊆ 𝐵)
5		sssucid 4560	. . 3 ⊢ 𝐵 ⊆ suc 𝐵
6	4, 5	sstrdi 3260	. 2 ⊢ ((𝐵 ∈ On ∧ 𝐴 ∈ 𝐵) → suc 𝐴 ⊆ suc 𝐵)
7		onelon 4529	. . 3 ⊢ ((𝐵 ∈ On ∧ 𝐴 ∈ 𝐵) → 𝐴 ∈ On)
8		elex 2833	. . . 4 ⊢ (𝐴 ∈ On → 𝐴 ∈ V)
9		sucexg 4645	. . . 4 ⊢ (𝐴 ∈ On → suc 𝐴 ∈ V)
10		suceq 4547	. . . . 5 ⊢ (𝑧 = 𝐴 → suc 𝑧 = suc 𝐴)
11		sucinc.1	. . . . 5 ⊢ 𝐹 = (𝑧 ∈ V ↦ suc 𝑧)
12	10, 11	fvmptg 5781	. . . 4 ⊢ ((𝐴 ∈ V ∧ suc 𝐴 ∈ V) → (𝐹‘𝐴) = suc 𝐴)
13	8, 9, 12	syl2anc 415	. . 3 ⊢ (𝐴 ∈ On → (𝐹‘𝐴) = suc 𝐴)
14	7, 13	syl 14	. 2 ⊢ ((𝐵 ∈ On ∧ 𝐴 ∈ 𝐵) → (𝐹‘𝐴) = suc 𝐴)
15		elex 2833	. . . 4 ⊢ (𝐵 ∈ On → 𝐵 ∈ V)
16		sucexg 4645	. . . 4 ⊢ (𝐵 ∈ On → suc 𝐵 ∈ V)
17		suceq 4547	. . . . 5 ⊢ (𝑧 = 𝐵 → suc 𝑧 = suc 𝐵)
18	17, 11	fvmptg 5781	. . . 4 ⊢ ((𝐵 ∈ V ∧ suc 𝐵 ∈ V) → (𝐹‘𝐵) = suc 𝐵)
19	15, 16, 18	syl2anc 415	. . 3 ⊢ (𝐵 ∈ On → (𝐹‘𝐵) = suc 𝐵)
20	19	adantr 276	. 2 ⊢ ((𝐵 ∈ On ∧ 𝐴 ∈ 𝐵) → (𝐹‘𝐵) = suc 𝐵)
21	6, 14, 20	3sstr4d 3293	1 ⊢ ((𝐵 ∈ On ∧ 𝐴 ∈ 𝐵) → (𝐹‘𝐴) ⊆ (𝐹‘𝐵))

This proof depends on syntax axioms:   → wi 4   ∧ wa 104   = wceq 1402   ∈ wcel 2209  Vcvv 2821   ⊆ wss 3220   ↦ cmpt 4192  Ord word 4507  Oncon0 4508  suc csuc 4510  ‘cfv 5377

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-io 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-14 2212  ax-ext 2220  ax-sep 4249  ax-pow 4311  ax-pr 4346  ax-un 4578

This proof depends on definitions:  df-bi 117  df-3an 1011  df-tru 1405  df-nf 1514  df-sb 1816  df-eu 2089  df-mo 2090  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-ral 2533  df-rex 2534  df-v 2823  df-sbc 3052  df-un 3224  df-in 3226  df-ss 3233  df-pw 3690  df-sn 3715  df-pr 3716  df-op 3718  df-uni 3936  df-br 4131  df-opab 4193  df-mpt 4194  df-tr 4230  df-id 4438  df-iord 4511  df-on 4513  df-suc 4516  df-xp 4780  df-rel 4781  df-cnv 4782  df-co 4783  df-dm 4784  df-iota 5337  df-fun 5379  df-fv 5385

This theorem is used by: (None)