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| Mirrors > Home > ILE Home > Th. List > sumdc | GIF version | ||
| Description: Decidability of a subset of upper integers. (Contributed by Jim Kingdon, 1-Jan-2022.) | 
| Ref | Expression | 
|---|---|
| sumdc.m | ⊢ (𝜑 → 𝑀 ∈ ℤ) | 
| sumdc.ss | ⊢ (𝜑 → 𝐴 ⊆ (ℤ≥‘𝑀)) | 
| sumdc.dc | ⊢ (𝜑 → ∀𝑥 ∈ (ℤ≥‘𝑀)DECID 𝑥 ∈ 𝐴) | 
| sumdc.n | ⊢ (𝜑 → 𝑁 ∈ ℤ) | 
| Ref | Expression | 
|---|---|
| sumdc | ⊢ (𝜑 → DECID 𝑁 ∈ 𝐴) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | sumdc.dc | . . 3 ⊢ (𝜑 → ∀𝑥 ∈ (ℤ≥‘𝑀)DECID 𝑥 ∈ 𝐴) | |
| 2 | eleq1 2259 | . . . . 5 ⊢ (𝑥 = 𝑁 → (𝑥 ∈ 𝐴 ↔ 𝑁 ∈ 𝐴)) | |
| 3 | 2 | dcbid 839 | . . . 4 ⊢ (𝑥 = 𝑁 → (DECID 𝑥 ∈ 𝐴 ↔ DECID 𝑁 ∈ 𝐴)) | 
| 4 | 3 | rspcv 2864 | . . 3 ⊢ (𝑁 ∈ (ℤ≥‘𝑀) → (∀𝑥 ∈ (ℤ≥‘𝑀)DECID 𝑥 ∈ 𝐴 → DECID 𝑁 ∈ 𝐴)) | 
| 5 | 1, 4 | mpan9 281 | . 2 ⊢ ((𝜑 ∧ 𝑁 ∈ (ℤ≥‘𝑀)) → DECID 𝑁 ∈ 𝐴) | 
| 6 | sumdc.ss | . . . . . 6 ⊢ (𝜑 → 𝐴 ⊆ (ℤ≥‘𝑀)) | |
| 7 | 6 | ssneld 3185 | . . . . 5 ⊢ (𝜑 → (¬ 𝑁 ∈ (ℤ≥‘𝑀) → ¬ 𝑁 ∈ 𝐴)) | 
| 8 | 7 | imp 124 | . . . 4 ⊢ ((𝜑 ∧ ¬ 𝑁 ∈ (ℤ≥‘𝑀)) → ¬ 𝑁 ∈ 𝐴) | 
| 9 | 8 | olcd 735 | . . 3 ⊢ ((𝜑 ∧ ¬ 𝑁 ∈ (ℤ≥‘𝑀)) → (𝑁 ∈ 𝐴 ∨ ¬ 𝑁 ∈ 𝐴)) | 
| 10 | df-dc 836 | . . 3 ⊢ (DECID 𝑁 ∈ 𝐴 ↔ (𝑁 ∈ 𝐴 ∨ ¬ 𝑁 ∈ 𝐴)) | |
| 11 | 9, 10 | sylibr 134 | . 2 ⊢ ((𝜑 ∧ ¬ 𝑁 ∈ (ℤ≥‘𝑀)) → DECID 𝑁 ∈ 𝐴) | 
| 12 | sumdc.m | . . . 4 ⊢ (𝜑 → 𝑀 ∈ ℤ) | |
| 13 | sumdc.n | . . . 4 ⊢ (𝜑 → 𝑁 ∈ ℤ) | |
| 14 | eluzdc 9684 | . . . 4 ⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → DECID 𝑁 ∈ (ℤ≥‘𝑀)) | |
| 15 | 12, 13, 14 | syl2anc 411 | . . 3 ⊢ (𝜑 → DECID 𝑁 ∈ (ℤ≥‘𝑀)) | 
| 16 | exmiddc 837 | . . 3 ⊢ (DECID 𝑁 ∈ (ℤ≥‘𝑀) → (𝑁 ∈ (ℤ≥‘𝑀) ∨ ¬ 𝑁 ∈ (ℤ≥‘𝑀))) | |
| 17 | 15, 16 | syl 14 | . 2 ⊢ (𝜑 → (𝑁 ∈ (ℤ≥‘𝑀) ∨ ¬ 𝑁 ∈ (ℤ≥‘𝑀))) | 
| 18 | 5, 11, 17 | mpjaodan 799 | 1 ⊢ (𝜑 → DECID 𝑁 ∈ 𝐴) | 
| Colors of variables: wff set class | 
| Syntax hints: ¬ wn 3 → wi 4 ∧ wa 104 ∨ wo 709 DECID wdc 835 = wceq 1364 ∈ wcel 2167 ∀wral 2475 ⊆ wss 3157 ‘cfv 5258 ℤcz 9326 ℤ≥cuz 9601 | 
| 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 615 ax-in2 616 ax-io 710 ax-5 1461 ax-7 1462 ax-gen 1463 ax-ie1 1507 ax-ie2 1508 ax-8 1518 ax-10 1519 ax-11 1520 ax-i12 1521 ax-bndl 1523 ax-4 1524 ax-17 1540 ax-i9 1544 ax-ial 1548 ax-i5r 1549 ax-13 2169 ax-14 2170 ax-ext 2178 ax-sep 4151 ax-pow 4207 ax-pr 4242 ax-un 4468 ax-setind 4573 ax-cnex 7970 ax-resscn 7971 ax-1cn 7972 ax-1re 7973 ax-icn 7974 ax-addcl 7975 ax-addrcl 7976 ax-mulcl 7977 ax-addcom 7979 ax-addass 7981 ax-distr 7983 ax-i2m1 7984 ax-0lt1 7985 ax-0id 7987 ax-rnegex 7988 ax-cnre 7990 ax-pre-ltirr 7991 ax-pre-ltwlin 7992 ax-pre-lttrn 7993 ax-pre-ltadd 7995 | 
| This theorem depends on definitions: df-bi 117 df-dc 836 df-3or 981 df-3an 982 df-tru 1367 df-fal 1370 df-nf 1475 df-sb 1777 df-eu 2048 df-mo 2049 df-clab 2183 df-cleq 2189 df-clel 2192 df-nfc 2328 df-ne 2368 df-nel 2463 df-ral 2480 df-rex 2481 df-reu 2482 df-rab 2484 df-v 2765 df-sbc 2990 df-dif 3159 df-un 3161 df-in 3163 df-ss 3170 df-pw 3607 df-sn 3628 df-pr 3629 df-op 3631 df-uni 3840 df-int 3875 df-br 4034 df-opab 4095 df-mpt 4096 df-id 4328 df-xp 4669 df-rel 4670 df-cnv 4671 df-co 4672 df-dm 4673 df-iota 5219 df-fun 5260 df-fv 5266 df-riota 5877 df-ov 5925 df-oprab 5926 df-mpo 5927 df-pnf 8063 df-mnf 8064 df-xr 8065 df-ltxr 8066 df-le 8067 df-sub 8199 df-neg 8200 df-inn 8991 df-n0 9250 df-z 9327 df-uz 9602 | 
| This theorem is referenced by: sumeq2 11524 prodeq2 11722 | 
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