Theorem elnns2 28784

Description: A positive surreal integer is a non-negative surreal integer greater than zero. (Contributed by Scott Fenton, 15-Apr-2025.)

Assertion

Ref	Expression
elnns2	⊢ (𝐴 ∈ ℕs ↔ (𝐴 ∈ ℕ0s ∧ 0s <s 𝐴))

Proof of Theorem elnns2

Step	Hyp	Ref	Expression
1		elnns 28783	. 2 ⊢ (𝐴 ∈ ℕs ↔ (𝐴 ∈ ℕ0s ∧ 𝐴 ≠ 0s ))
2		nesym 3015	. . . . 5 ⊢ (𝐴 ≠ 0s ↔ ¬ 0s = 𝐴)
3		n0sge0 28781	. . . . . . . 8 ⊢ (𝐴 ∈ ℕ0s → 0s ≤s 𝐴)
4		0no 28252	. . . . . . . . 9 ⊢ 0s ∈ No
5		n0no 28766	. . . . . . . . 9 ⊢ (𝐴 ∈ ℕ0s → 𝐴 ∈ No)
6		lesloe 28168	. . . . . . . . 9 ⊢ (( 0s ∈ No ∧ 𝐴 ∈ No) → ( 0s ≤s 𝐴 ↔ ( 0s <s 𝐴 ∨ 0s = 𝐴)))
7	4, 5, 6	sylancr 599	. . . . . . . 8 ⊢ (𝐴 ∈ ℕ0s → ( 0s ≤s 𝐴 ↔ ( 0s <s 𝐴 ∨ 0s = 𝐴)))
8	3, 7	mpbid 235	. . . . . . 7 ⊢ (𝐴 ∈ ℕ0s → ( 0s <s 𝐴 ∨ 0s = 𝐴))
9	8	orcomd 885	. . . . . 6 ⊢ (𝐴 ∈ ℕ0s → ( 0s = 𝐴 ∨ 0s <s 𝐴))
10	9	ord 878	. . . . 5 ⊢ (𝐴 ∈ ℕ0s → (¬ 0s = 𝐴 → 0s <s 𝐴))
11	2, 10	biimtrid 245	. . . 4 ⊢ (𝐴 ∈ ℕ0s → (𝐴 ≠ 0s → 0s <s 𝐴))
12		gt0ne0s 28261	. . . 4 ⊢ ( 0s <s 𝐴 → 𝐴 ≠ 0s )
13	11, 12	impbid1 228	. . 3 ⊢ (𝐴 ∈ ℕ0s → (𝐴 ≠ 0s ↔ 0s <s 𝐴))
14	13	pm5.32i 585	. 2 ⊢ ((𝐴 ∈ ℕ0s ∧ 𝐴 ≠ 0s ) ↔ (𝐴 ∈ ℕ0s ∧ 0s <s 𝐴))
15	1, 14	bitri 278	1 ⊢ (𝐴 ∈ ℕs ↔ (𝐴 ∈ ℕ0s ∧ 0s <s 𝐴))

This proof depends on syntax axioms:  ¬ wn 3   ↔ wb 209   ∧ wa 401   ∨ wo 861   = wceq 1570   ∈ wcel 2147   ≠ wne 2959   class class class wbr 5108  Nocsur 28054   <s clts 28055   ≤s cles 28158   0_s c0s 28248  ℕ_0scn0s 28755  ℕ_scnns 28756

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1945  ax-6 2002  ax-7 2043  ax-8 2149  ax-9 2157  ax-10 2180  ax-11 2197  ax-12 2216  ax-ext 2735  ax-rep 5238  ax-sep 5255  ax-nul 5266  ax-pow 5334  ax-pr 5398  ax-un 7783

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3or 1104  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1813  df-nf 1817  df-sb 2102  df-mo 2567  df-eu 2597  df-clab 2742  df-cleq 2755  df-clel 2839  df-nfc 2913  df-ne 2960  df-ral 3081  df-rex 3091  df-rmo 3369  df-reu 3370  df-rab 3417  df-v 3456  df-sbc 3743  df-csb 3852  df-ss 3901  df-pss 4017  df-dif 4050  df-in 4094  df-un 4154  df-nul 4282  df-if 4486  df-pw 4562  df-sn 4589  df-pr 4591  df-tp 4593  df-op 4841  df-ot 4864  df-uni 4873  df-int 4913  df-iun 4958  df-br 5109  df-opab 5174  df-mpt 5193  df-tr 5219  df-id 5553  df-eprel 5558  df-po 5566  df-so 5567  df-fr 5611  df-se 5612  df-we 5613  df-xp 5664  df-rel 5665  df-cnv 5666  df-co 5667  df-dm 5668  df-rn 5669  df-res 5670  df-ima 5671  df-pred 6330  df-ord 6391  df-on 6392  df-lim 6393  df-suc 6394  df-iota 6520  df-fun 6568  df-fn 6569  df-f 6570  df-f1 6571  df-fo 6572  df-f1o 6573  df-fv 6574  df-riota 7408  df-ov 7454  df-oprab 7455  df-mpo 7456  df-om 7912  df-1st 8035  df-2nd 8036  df-frecs 8337  df-wrecs 8368  df-recs 8417  df-rdg 8456  df-1o 8514  df-2o 8515  df-nadd 8713  df-no 28057  df-lts 28058  df-bday 28059  df-les 28159  df-slts 28201  df-cuts 28203  df-0s 28250  df-1s 28251  df-made 28270  df-old 28271  df-left 28273  df-right 28274  df-norec2 28392  df-adds 28403  df-n0s 28757  df-nns 28758

This theorem is used by:  nnaddscl  28789  nnmulscl  28790