HomeHome Metamath Proof Explorer < Previous   Next >
Related theorems
GIF version

Theorem ordnbtwn 2316
Description: There is no set between an ordinal class and its successor. Generalized Proposition 7.25 of [TakeutiZaring] p. 41.
Assertion
Ref Expression
ordnbtwn (Ord A → ¬ (ABB ∈ suc A))

Proof of Theorem ordnbtwn
StepHypRef Expression
1 ordn2lp 2219 . . . 4 (Ord A → ¬ (ABBA))
2 ordeirr 2217 . . . 4 (Ord A → ¬ AA)
31, 2jca 236 . . 3 (Ord A → (¬ (ABBA) ∧ ¬ AA))
4 ioran 254 . . 3 (¬ ((ABBA) ∨ AA) ↔ (¬ (ABBA) ∧ ¬ AA))
53, 4sylibr 175 . 2 (Ord A → ¬ ((ABBA) ∨ AA))
6 elsuci 2289 . . . . 5 (B ∈ suc A → (BAB = A))
76anim2i 270 . . . 4 ((ABB ∈ suc A) → (AB ∧ (BAB = A)))
8 andi 456 . . . 4 ((AB ∧ (BAB = A)) ↔ ((ABBA) ∨ (ABB = A)))
97, 8sylib 173 . . 3 ((ABB ∈ suc A) → ((ABBA) ∨ (ABB = A)))
10 eleq2 1150 . . . . 5 (B = A → (ABAA))
1110biimpac 326 . . . 4 ((ABB = A) → AA)
1211orim2i 273 . . 3 (((ABBA) ∨ (ABB = A)) → ((ABBA) ∨ AA))
139, 12syl 12 . 2 ((ABB ∈ suc A) → ((ABBA) ∨ AA))
145, 13nsyl 102 1 (Ord A → ¬ (ABB ∈ suc A))
Colors of variables: wff set class
Syntax hints:  ¬ wn 1   → wi 2   ∨ wo 195   ∧ wa 196   = wceq 1091   ∈ wcel 1092  Ord word 2198  suc csuc 2201
This theorem is referenced by:  onnbtwn 2317  ordsucss 2320
This theorem was proved from axioms:  ax-1 3  ax-2 4  ax-3 5  ax-mp 6  ax-4 673  ax-5 674  ax-6 675  ax-7 676  ax-gen 677  ax-8 798  ax-9 799  ax-10 800  ax-11 801  ax-12 802  ax-13 804  ax-14 805  ax-16 922  ax-17 925  ax-ext 1074  ax-rep 1075  ax-pow 1077
This theorem depends on definitions:  df-bi 128  df-or 197  df-an 198  df-ex 679  df-sb 853  df-clab 1093  df-cleq 1097  df-clel 1099  df-ral 1205  df-rex 1206  df-v 1349  df-dif 1489  df-un 1490  df-in 1491  df-ss 1492  df-nul 1708  df-pw 1799  df-sn 1811  df-pr 1812  df-op 1815  df-uni 1920  df-tr 2042  df-br 2063  df-opab 2098  df-eprel 2122  df-fr 2169  df-we 2186  df-ord 2202  df-suc 2205
metamath.org