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Theorem inton 4490
Description: The intersection of the class of ordinal numbers is the empty set. (Contributed by NM, 20-Oct-2003.)
Assertion
Ref Expression
inton On = ∅

Proof of Theorem inton
StepHypRef Expression
1 0elon 4489 . 2 ∅ ∈ On
2 int0el 3958 . 2 (∅ ∈ On → On = ∅)
31, 2ax-mp 5 1 On = ∅
Colors of variables: wff set class
Syntax hints:   = wceq 1397  wcel 2202  c0 3494   cint 3928  Oncon0 4460
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 619  ax-in2 620  ax-io 716  ax-5 1495  ax-7 1496  ax-gen 1497  ax-ie1 1541  ax-ie2 1542  ax-8 1552  ax-10 1553  ax-11 1554  ax-i12 1555  ax-bndl 1557  ax-4 1558  ax-17 1574  ax-i9 1578  ax-ial 1582  ax-i5r 1583  ax-ext 2213  ax-nul 4215
This theorem depends on definitions:  df-bi 117  df-tru 1400  df-nf 1509  df-sb 1811  df-clab 2218  df-cleq 2224  df-clel 2227  df-nfc 2363  df-ral 2515  df-rex 2516  df-v 2804  df-dif 3202  df-in 3206  df-ss 3213  df-nul 3495  df-pw 3654  df-uni 3894  df-int 3929  df-tr 4188  df-iord 4463  df-on 4465
This theorem is referenced by: (None)
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