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Mirrors > Home > MPE Home > Th. List > niex | Structured version Visualization version GIF version |
Description: The class of positive integers is a set. (Contributed by NM, 15-Aug-1995.) (New usage is discouraged.) |
Ref | Expression |
---|---|
niex | ⊢ N ∈ V |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | omex 9109 | . 2 ⊢ ω ∈ V | |
2 | df-ni 10297 | . . 3 ⊢ N = (ω ∖ {∅}) | |
3 | difss 4111 | . . 3 ⊢ (ω ∖ {∅}) ⊆ ω | |
4 | 2, 3 | eqsstri 4004 | . 2 ⊢ N ⊆ ω |
5 | 1, 4 | ssexi 5229 | 1 ⊢ N ∈ V |
Colors of variables: wff setvar class |
Syntax hints: ∈ wcel 2113 Vcvv 3497 ∖ cdif 3936 ∅c0 4294 {csn 4570 ωcom 7583 Ncnpi 10269 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1795 ax-4 1809 ax-5 1910 ax-6 1969 ax-7 2014 ax-8 2115 ax-9 2123 ax-10 2144 ax-11 2160 ax-12 2176 ax-ext 2796 ax-sep 5206 ax-nul 5213 ax-pr 5333 ax-un 7464 ax-inf2 9107 |
This theorem depends on definitions: df-bi 209 df-an 399 df-or 844 df-3or 1084 df-3an 1085 df-tru 1539 df-ex 1780 df-nf 1784 df-sb 2069 df-mo 2621 df-eu 2653 df-clab 2803 df-cleq 2817 df-clel 2896 df-nfc 2966 df-ne 3020 df-ral 3146 df-rex 3147 df-rab 3150 df-v 3499 df-sbc 3776 df-dif 3942 df-un 3944 df-in 3946 df-ss 3955 df-pss 3957 df-nul 4295 df-if 4471 df-pw 4544 df-sn 4571 df-pr 4573 df-tp 4575 df-op 4577 df-uni 4842 df-br 5070 df-opab 5132 df-tr 5176 df-eprel 5468 df-po 5477 df-so 5478 df-fr 5517 df-we 5519 df-ord 6197 df-on 6198 df-lim 6199 df-suc 6200 df-om 7584 df-ni 10297 |
This theorem is referenced by: enqex 10347 nqex 10348 |
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