![]() |
Metamath Proof Explorer |
< Previous
Next >
Nearby theorems |
|
Mirrors > Home > MPE Home > Th. List > nnacl | Structured version Visualization version GIF version |
Description: Closure of addition of natural numbers. Proposition 8.9 of [TakeutiZaring] p. 59. (Contributed by NM, 20-Sep-1995.) (Proof shortened by Andrew Salmon, 22-Oct-2011.) |
Ref | Expression |
---|---|
nnacl | ⊢ ((𝐴 ∈ ω ∧ 𝐵 ∈ ω) → (𝐴 +o 𝐵) ∈ ω) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | oveq2 6932 | . . . . 5 ⊢ (𝑥 = 𝐵 → (𝐴 +o 𝑥) = (𝐴 +o 𝐵)) | |
2 | 1 | eleq1d 2844 | . . . 4 ⊢ (𝑥 = 𝐵 → ((𝐴 +o 𝑥) ∈ ω ↔ (𝐴 +o 𝐵) ∈ ω)) |
3 | 2 | imbi2d 332 | . . 3 ⊢ (𝑥 = 𝐵 → ((𝐴 ∈ ω → (𝐴 +o 𝑥) ∈ ω) ↔ (𝐴 ∈ ω → (𝐴 +o 𝐵) ∈ ω))) |
4 | oveq2 6932 | . . . . 5 ⊢ (𝑥 = ∅ → (𝐴 +o 𝑥) = (𝐴 +o ∅)) | |
5 | 4 | eleq1d 2844 | . . . 4 ⊢ (𝑥 = ∅ → ((𝐴 +o 𝑥) ∈ ω ↔ (𝐴 +o ∅) ∈ ω)) |
6 | oveq2 6932 | . . . . 5 ⊢ (𝑥 = 𝑦 → (𝐴 +o 𝑥) = (𝐴 +o 𝑦)) | |
7 | 6 | eleq1d 2844 | . . . 4 ⊢ (𝑥 = 𝑦 → ((𝐴 +o 𝑥) ∈ ω ↔ (𝐴 +o 𝑦) ∈ ω)) |
8 | oveq2 6932 | . . . . 5 ⊢ (𝑥 = suc 𝑦 → (𝐴 +o 𝑥) = (𝐴 +o suc 𝑦)) | |
9 | 8 | eleq1d 2844 | . . . 4 ⊢ (𝑥 = suc 𝑦 → ((𝐴 +o 𝑥) ∈ ω ↔ (𝐴 +o suc 𝑦) ∈ ω)) |
10 | nna0 7970 | . . . . . 6 ⊢ (𝐴 ∈ ω → (𝐴 +o ∅) = 𝐴) | |
11 | 10 | eleq1d 2844 | . . . . 5 ⊢ (𝐴 ∈ ω → ((𝐴 +o ∅) ∈ ω ↔ 𝐴 ∈ ω)) |
12 | 11 | ibir 260 | . . . 4 ⊢ (𝐴 ∈ ω → (𝐴 +o ∅) ∈ ω) |
13 | peano2 7366 | . . . . . 6 ⊢ ((𝐴 +o 𝑦) ∈ ω → suc (𝐴 +o 𝑦) ∈ ω) | |
14 | nnasuc 7972 | . . . . . . 7 ⊢ ((𝐴 ∈ ω ∧ 𝑦 ∈ ω) → (𝐴 +o suc 𝑦) = suc (𝐴 +o 𝑦)) | |
15 | 14 | eleq1d 2844 | . . . . . 6 ⊢ ((𝐴 ∈ ω ∧ 𝑦 ∈ ω) → ((𝐴 +o suc 𝑦) ∈ ω ↔ suc (𝐴 +o 𝑦) ∈ ω)) |
16 | 13, 15 | syl5ibr 238 | . . . . 5 ⊢ ((𝐴 ∈ ω ∧ 𝑦 ∈ ω) → ((𝐴 +o 𝑦) ∈ ω → (𝐴 +o suc 𝑦) ∈ ω)) |
17 | 16 | expcom 404 | . . . 4 ⊢ (𝑦 ∈ ω → (𝐴 ∈ ω → ((𝐴 +o 𝑦) ∈ ω → (𝐴 +o suc 𝑦) ∈ ω))) |
18 | 5, 7, 9, 12, 17 | finds2 7374 | . . 3 ⊢ (𝑥 ∈ ω → (𝐴 ∈ ω → (𝐴 +o 𝑥) ∈ ω)) |
19 | 3, 18 | vtoclga 3474 | . 2 ⊢ (𝐵 ∈ ω → (𝐴 ∈ ω → (𝐴 +o 𝐵) ∈ ω)) |
20 | 19 | impcom 398 | 1 ⊢ ((𝐴 ∈ ω ∧ 𝐵 ∈ ω) → (𝐴 +o 𝐵) ∈ ω) |
Colors of variables: wff setvar class |
Syntax hints: → wi 4 ∧ wa 386 = wceq 1601 ∈ wcel 2107 ∅c0 4141 suc csuc 5980 (class class class)co 6924 ωcom 7345 +o coa 7842 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1839 ax-4 1853 ax-5 1953 ax-6 2021 ax-7 2055 ax-8 2109 ax-9 2116 ax-10 2135 ax-11 2150 ax-12 2163 ax-13 2334 ax-ext 2754 ax-sep 5019 ax-nul 5027 ax-pow 5079 ax-pr 5140 ax-un 7228 |
This theorem depends on definitions: df-bi 199 df-an 387 df-or 837 df-3or 1072 df-3an 1073 df-tru 1605 df-ex 1824 df-nf 1828 df-sb 2012 df-mo 2551 df-eu 2587 df-clab 2764 df-cleq 2770 df-clel 2774 df-nfc 2921 df-ne 2970 df-ral 3095 df-rex 3096 df-reu 3097 df-rab 3099 df-v 3400 df-sbc 3653 df-csb 3752 df-dif 3795 df-un 3797 df-in 3799 df-ss 3806 df-pss 3808 df-nul 4142 df-if 4308 df-pw 4381 df-sn 4399 df-pr 4401 df-tp 4403 df-op 4405 df-uni 4674 df-iun 4757 df-br 4889 df-opab 4951 df-mpt 4968 df-tr 4990 df-id 5263 df-eprel 5268 df-po 5276 df-so 5277 df-fr 5316 df-we 5318 df-xp 5363 df-rel 5364 df-cnv 5365 df-co 5366 df-dm 5367 df-rn 5368 df-res 5369 df-ima 5370 df-pred 5935 df-ord 5981 df-on 5982 df-lim 5983 df-suc 5984 df-iota 6101 df-fun 6139 df-fn 6140 df-f 6141 df-f1 6142 df-fo 6143 df-f1o 6144 df-fv 6145 df-ov 6927 df-oprab 6928 df-mpt2 6929 df-om 7346 df-wrecs 7691 df-recs 7753 df-rdg 7791 df-oadd 7849 |
This theorem is referenced by: nnmcl 7978 nnacli 7980 nnarcl 7982 nnaord 7985 nnawordi 7987 nnaass 7988 nndi 7989 nnaword 7993 nnawordex 8003 oaabslem 8009 unfilem1 8514 unfi 8517 nnacda 9360 ficardun 9361 ficardun2 9362 pwsdompw 9363 addclpi 10051 hashgadd 13487 hashdom 13489 finxpreclem4 33833 |
Copyright terms: Public domain | W3C validator |