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Theorem nodense 28054
Description: Given two distinct surreals with the same birthday, there is an older surreal lying between the two of them. Axiom SD of [Alling] p. 184. (Contributed by Scott Fenton, 16-Jun-2011.)
Assertion
Ref Expression
nodense (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → ∃𝑥 ∈ No ((bday‘𝑥) ∈ (bday‘𝐴) ∧ 𝐴 <s 𝑥 ∧ 𝑥 <s 𝐵))
Distinct variable groups:   𝑥,𝐴   𝑥,𝐵

Proof of Theorem nodense
Dummy variables 𝑎 𝑦 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 nodenselem6 28051 . 2 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → (𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) ∈ No)
2 bdayval 28010 . . . . 5 ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) ∈ No → (bday‘(𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})) = dom (𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}))
31, 2syl 18 . . . 4 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → (bday‘(𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})) = dom (𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}))
4 dmres 6002 . . . . 5 dom (𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) = (∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} ∩ dom 𝐴)
5 nodenselem5 28050 . . . . . . . 8 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} ∈ (bday‘𝐴))
6 bdayfo 28039 . . . . . . . . . . 11 bday:No–onto→On
7 fof 6796 . . . . . . . . . . 11 (bday:No–onto→On → bday:No⟶On)
86, 7ax-mp 5 . . . . . . . . . 10 bday:No⟶On
9 0elon 6418 . . . . . . . . . 10 ∅ ∈ On
108, 9f0cli 7098 . . . . . . . . 9 (bday‘𝐴) ∈ On
1110onelssi 6479 . . . . . . . 8 (∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} ∈ (bday‘𝐴) → ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} ⊆ (bday‘𝐴))
125, 11syl 18 . . . . . . 7 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} ⊆ (bday‘𝐴))
13 bdayval 28010 . . . . . . . 8 (𝐴 ∈ No → (bday‘𝐴) = dom 𝐴)
1413ad2antrr 739 . . . . . . 7 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → (bday‘𝐴) = dom 𝐴)
1512, 14sseqtrd 3944 . . . . . 6 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} ⊆ dom 𝐴)
16 dfss2 4094 . . . . . 6 (∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} ⊆ dom 𝐴 ↔ (∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} ∩ dom 𝐴) = ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})
1715, 16sylib 221 . . . . 5 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → (∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} ∩ dom 𝐴) = ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})
184, 17eqtrid 2807 . . . 4 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → dom (𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) = ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})
193, 18eqtrd 2795 . . 3 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → (bday‘(𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})) = ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})
2019, 5eqeltrd 2860 . 2 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → (bday‘(𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})) ∈ (bday‘𝐴))
21 nodenselem4 28049 . . . . 5 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ 𝐴 <s 𝐵) → ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} ∈ On)
2221adantrl 729 . . . 4 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} ∈ On)
23 nodenselem8 28053 . . . . . . . . . . . . 13 ((𝐴 ∈ No ∧ 𝐵 ∈ No ∧ (bday‘𝐴) = (bday‘𝐵)) → (𝐴 <s 𝐵 ↔ ((𝐴‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) = 1o ∧ (𝐵‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) = 2o)))
2423biimpd 232 . . . . . . . . . . . 12 ((𝐴 ∈ No ∧ 𝐵 ∈ No ∧ (bday‘𝐴) = (bday‘𝐵)) → (𝐴 <s 𝐵 → ((𝐴‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) = 1o ∧ (𝐵‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) = 2o)))
25243expia 1139 . . . . . . . . . . 11 ((𝐴 ∈ No ∧ 𝐵 ∈ No) → ((bday‘𝐴) = (bday‘𝐵) → (𝐴 <s 𝐵 → ((𝐴‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) = 1o ∧ (𝐵‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) = 2o))))
2625imp32 424 . . . . . . . . . 10 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → ((𝐴‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) = 1o ∧ (𝐵‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) = 2o))
2726simpld 500 . . . . . . . . 9 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → (𝐴‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) = 1o)
28 eqid 2760 . . . . . . . . 9 ∅ = ∅
2927, 28jctir 530 . . . . . . . 8 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → ((𝐴‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) = 1o ∧ ∅ = ∅))
30293mix1d 1355 . . . . . . 7 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → (((𝐴‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) = 1o ∧ ∅ = ∅) ∨ ((𝐴‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) = 1o ∧ ∅ = 2o) ∨ ((𝐴‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) = ∅ ∧ ∅ = 2o)))
31 fvex 6898 . . . . . . . 8 (𝐴‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) ∈ V
32 0ex 5260 . . . . . . . 8 ∅ ∈ V
3331, 32brtp 5496 . . . . . . 7 ((𝐴‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}){⟨1o, ∅⟩, ⟨1o, 2o⟩, ⟨∅, 2o⟩}∅ ↔ (((𝐴‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) = 1o ∧ ∅ = ∅) ∨ ((𝐴‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) = 1o ∧ ∅ = 2o) ∨ ((𝐴‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) = ∅ ∧ ∅ = 2o)))
3430, 33sylibr 237 . . . . . 6 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → (𝐴‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}){⟨1o, ∅⟩, ⟨1o, 2o⟩, ⟨∅, 2o⟩}∅)
3519fveq2d 6889 . . . . . . 7 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘(bday‘(𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}))) = ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}))
36 fvnobday 28040 . . . . . . . 8 ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) ∈ No → ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘(bday‘(𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}))) = ∅)
371, 36syl 18 . . . . . . 7 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘(bday‘(𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}))) = ∅)
3835, 37eqtr3d 2797 . . . . . 6 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) = ∅)
3934, 38breqtrrd 5132 . . . . 5 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → (𝐴‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}){⟨1o, ∅⟩, ⟨1o, 2o⟩, ⟨∅, 2o⟩} ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}))
40 fvres 6904 . . . . . . 7 (𝑦 ∈ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} → ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑦) = (𝐴‘𝑦))
4140eqcomd 2766 . . . . . 6 (𝑦 ∈ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} → (𝐴‘𝑦) = ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑦))
4241rgen 3078 . . . . 5 ∀𝑦 ∈ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} (𝐴‘𝑦) = ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑦)
4339, 42jctil 529 . . . 4 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → (∀𝑦 ∈ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} (𝐴‘𝑦) = ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑦) ∧ (𝐴‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}){⟨1o, ∅⟩, ⟨1o, 2o⟩, ⟨∅, 2o⟩} ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})))
44 raleq 3316 . . . . . 6 (𝑥 = ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} → (∀𝑦 ∈ 𝑥 (𝐴‘𝑦) = ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑦) ↔ ∀𝑦 ∈ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} (𝐴‘𝑦) = ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑦)))
45 fveq2 6885 . . . . . . 7 (𝑥 = ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} → (𝐴‘𝑥) = (𝐴‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}))
46 fveq2 6885 . . . . . . 7 (𝑥 = ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} → ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑥) = ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}))
4745, 46breq12d 5115 . . . . . 6 (𝑥 = ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} → ((𝐴‘𝑥){⟨1o, ∅⟩, ⟨1o, 2o⟩, ⟨∅, 2o⟩} ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑥) ↔ (𝐴‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}){⟨1o, ∅⟩, ⟨1o, 2o⟩, ⟨∅, 2o⟩} ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})))
4844, 47anbi12d 644 . . . . 5 (𝑥 = ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} → ((∀𝑦 ∈ 𝑥 (𝐴‘𝑦) = ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑦) ∧ (𝐴‘𝑥){⟨1o, ∅⟩, ⟨1o, 2o⟩, ⟨∅, 2o⟩} ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑥)) ↔ (∀𝑦 ∈ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} (𝐴‘𝑦) = ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑦) ∧ (𝐴‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}){⟨1o, ∅⟩, ⟨1o, 2o⟩, ⟨∅, 2o⟩} ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}))))
4948rspcev 3576 . . . 4 ((∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} ∈ On ∧ (∀𝑦 ∈ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} (𝐴‘𝑦) = ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑦) ∧ (𝐴‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}){⟨1o, ∅⟩, ⟨1o, 2o⟩, ⟨∅, 2o⟩} ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}))) → ∃𝑥 ∈ On (∀𝑦 ∈ 𝑥 (𝐴‘𝑦) = ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑦) ∧ (𝐴‘𝑥){⟨1o, ∅⟩, ⟨1o, 2o⟩, ⟨∅, 2o⟩} ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑥)))
5022, 43, 49syl2anc 596 . . 3 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → ∃𝑥 ∈ On (∀𝑦 ∈ 𝑥 (𝐴‘𝑦) = ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑦) ∧ (𝐴‘𝑥){⟨1o, ∅⟩, ⟨1o, 2o⟩, ⟨∅, 2o⟩} ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑥)))
51 simpll 779 . . . 4 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → 𝐴 ∈ No)
52 ltsval 28009 . . . 4 ((𝐴 ∈ No ∧ (𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) ∈ No) → (𝐴 <s (𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) ↔ ∃𝑥 ∈ On (∀𝑦 ∈ 𝑥 (𝐴‘𝑦) = ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑦) ∧ (𝐴‘𝑥){⟨1o, ∅⟩, ⟨1o, 2o⟩, ⟨∅, 2o⟩} ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑥))))
5351, 1, 52syl2anc 596 . . 3 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → (𝐴 <s (𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) ↔ ∃𝑥 ∈ On (∀𝑦 ∈ 𝑥 (𝐴‘𝑦) = ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑦) ∧ (𝐴‘𝑥){⟨1o, ∅⟩, ⟨1o, 2o⟩, ⟨∅, 2o⟩} ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑥))))
5450, 53mpbird 260 . 2 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → 𝐴 <s (𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}))
5541adantl 487 . . . . . 6 ((((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) ∧ 𝑦 ∈ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) → (𝐴‘𝑦) = ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑦))
56 nodenselem7 28052 . . . . . . 7 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → (𝑦 ∈ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} → (𝐴‘𝑦) = (𝐵‘𝑦)))
5756imp 412 . . . . . 6 ((((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) ∧ 𝑦 ∈ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) → (𝐴‘𝑦) = (𝐵‘𝑦))
5855, 57eqtr3d 2797 . . . . 5 ((((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) ∧ 𝑦 ∈ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) → ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑦) = (𝐵‘𝑦))
5958ralrimiva 3154 . . . 4 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → ∀𝑦 ∈ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑦) = (𝐵‘𝑦))
6026simprd 501 . . . . . . . 8 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → (𝐵‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) = 2o)
6160, 28jctil 529 . . . . . . 7 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → (∅ = ∅ ∧ (𝐵‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) = 2o))
62613mix3d 1357 . . . . . 6 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → ((∅ = 1o ∧ (𝐵‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) = ∅) ∨ (∅ = 1o ∧ (𝐵‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) = 2o) ∨ (∅ = ∅ ∧ (𝐵‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) = 2o)))
63 fvex 6898 . . . . . . 7 (𝐵‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) ∈ V
6432, 63brtp 5496 . . . . . 6 (∅{⟨1o, ∅⟩, ⟨1o, 2o⟩, ⟨∅, 2o⟩} (𝐵‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) ↔ ((∅ = 1o ∧ (𝐵‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) = ∅) ∨ (∅ = 1o ∧ (𝐵‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) = 2o) ∨ (∅ = ∅ ∧ (𝐵‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) = 2o)))
6562, 64sylibr 237 . . . . 5 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → ∅{⟨1o, ∅⟩, ⟨1o, 2o⟩, ⟨∅, 2o⟩} (𝐵‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}))
6638, 65eqbrtrd 5126 . . . 4 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}){⟨1o, ∅⟩, ⟨1o, 2o⟩, ⟨∅, 2o⟩} (𝐵‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}))
67 raleq 3316 . . . . . 6 (𝑥 = ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} → (∀𝑦 ∈ 𝑥 ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑦) = (𝐵‘𝑦) ↔ ∀𝑦 ∈ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑦) = (𝐵‘𝑦)))
68 fveq2 6885 . . . . . . 7 (𝑥 = ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} → (𝐵‘𝑥) = (𝐵‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}))
6946, 68breq12d 5115 . . . . . 6 (𝑥 = ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} → (((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑥){⟨1o, ∅⟩, ⟨1o, 2o⟩, ⟨∅, 2o⟩} (𝐵‘𝑥) ↔ ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}){⟨1o, ∅⟩, ⟨1o, 2o⟩, ⟨∅, 2o⟩} (𝐵‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})))
7067, 69anbi12d 644 . . . . 5 (𝑥 = ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} → ((∀𝑦 ∈ 𝑥 ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑦) = (𝐵‘𝑦) ∧ ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑥){⟨1o, ∅⟩, ⟨1o, 2o⟩, ⟨∅, 2o⟩} (𝐵‘𝑥)) ↔ (∀𝑦 ∈ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑦) = (𝐵‘𝑦) ∧ ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}){⟨1o, ∅⟩, ⟨1o, 2o⟩, ⟨∅, 2o⟩} (𝐵‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}))))
7170rspcev 3576 . . . 4 ((∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} ∈ On ∧ (∀𝑦 ∈ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)} ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑦) = (𝐵‘𝑦) ∧ ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}){⟨1o, ∅⟩, ⟨1o, 2o⟩, ⟨∅, 2o⟩} (𝐵‘∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}))) → ∃𝑥 ∈ On (∀𝑦 ∈ 𝑥 ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑦) = (𝐵‘𝑦) ∧ ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑥){⟨1o, ∅⟩, ⟨1o, 2o⟩, ⟨∅, 2o⟩} (𝐵‘𝑥)))
7222, 59, 66, 71syl12anc 850 . . 3 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → ∃𝑥 ∈ On (∀𝑦 ∈ 𝑥 ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑦) = (𝐵‘𝑦) ∧ ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑥){⟨1o, ∅⟩, ⟨1o, 2o⟩, ⟨∅, 2o⟩} (𝐵‘𝑥)))
73 simplr 781 . . . 4 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → 𝐵 ∈ No)
74 ltsval 28009 . . . 4 (((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) ∈ No ∧ 𝐵 ∈ No) → ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) <s 𝐵 ↔ ∃𝑥 ∈ On (∀𝑦 ∈ 𝑥 ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑦) = (𝐵‘𝑦) ∧ ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑥){⟨1o, ∅⟩, ⟨1o, 2o⟩, ⟨∅, 2o⟩} (𝐵‘𝑥))))
751, 73, 74syl2anc 596 . . 3 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) <s 𝐵 ↔ ∃𝑥 ∈ On (∀𝑦 ∈ 𝑥 ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑦) = (𝐵‘𝑦) ∧ ((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})‘𝑥){⟨1o, ∅⟩, ⟨1o, 2o⟩, ⟨∅, 2o⟩} (𝐵‘𝑥))))
7672, 75mpbird 260 . 2 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → (𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) <s 𝐵)
77 fveq2 6885 . . . . 5 (𝑥 = (𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) → (bday‘𝑥) = (bday‘(𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})))
7877eleq1d 2845 . . . 4 (𝑥 = (𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) → ((bday‘𝑥) ∈ (bday‘𝐴) ↔ (bday‘(𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})) ∈ (bday‘𝐴)))
79 breq2 5106 . . . 4 (𝑥 = (𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) → (𝐴 <s 𝑥 ↔ 𝐴 <s (𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})))
80 breq1 5105 . . . 4 (𝑥 = (𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) → (𝑥 <s 𝐵 ↔ (𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) <s 𝐵))
8178, 79, 803anbi123d 1464 . . 3 (𝑥 = (𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) → (((bday‘𝑥) ∈ (bday‘𝐴) ∧ 𝐴 <s 𝑥 ∧ 𝑥 <s 𝐵) ↔ ((bday‘(𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})) ∈ (bday‘𝐴) ∧ 𝐴 <s (𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) ∧ (𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) <s 𝐵)))
8281rspcev 3576 . 2 (((𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) ∈ No ∧ ((bday‘(𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)})) ∈ (bday‘𝐴) ∧ 𝐴 <s (𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) ∧ (𝐴 ↾ ∩ {𝑎 ∈ On ∣ (𝐴‘𝑎) ≠ (𝐵‘𝑎)}) <s 𝐵)) → ∃𝑥 ∈ No ((bday‘𝑥) ∈ (bday‘𝐴) ∧ 𝐴 <s 𝑥 ∧ 𝑥 <s 𝐵))
831, 20, 54, 76, 82syl13anc 1399 1 (((𝐴 ∈ No ∧ 𝐵 ∈ No) ∧ ((bday‘𝐴) = (bday‘𝐵) ∧ 𝐴 <s 𝐵)) → ∃𝑥 ∈ No ((bday‘𝑥) ∈ (bday‘𝐴) ∧ 𝐴 <s 𝑥 ∧ 𝑥 <s 𝐵))
Colors of variables:    wff setvar class
This proof depends on syntax axioms:   → wi 4   ↔ wb 209   ∧ wa 401   ∨ w3o 1102   ∧ w3a 1103   = wceq 1569   ∈ wcel 2144   ≠ wne 2955  ∀wral 3076  ∃wrex 3086  {crab 3412   ⊆ wss 3895   ∩ cin 4089  ∅c0 4278  {ctp 4588  ⟨cop 4834  ∩ cint 4906   class class class wbr 5102  dom cdm 5650   ↾ cres 5652  Oncon0 6362  ⟶wf 6534  –onto→wfo 6536  ‘cfv 6538  1oc1o 8472  2oc2o 8473  Nocsur 28002   <s clts 28003  bdaycbday 28004
This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1827  ax-4 1841  ax-5 1942  ax-6 1999  ax-7 2040  ax-8 2146  ax-9 2154  ax-10 2177  ax-11 2193  ax-12 2212  ax-ext 2732  ax-sep 5248  ax-nul 5259  ax-pow 5326  ax-pr 5390  ax-un 7751
This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3or 1104  df-3an 1105  df-tru 1572  df-fal 1582  df-ex 1812  df-nf 1816  df-sb 2099  df-mo 2564  df-eu 2594  df-clab 2739  df-cleq 2752  df-clel 2835  df-nfc 2909  df-ne 2956  df-ral 3077  df-rex 3087  df-rab 3413  df-v 3452  df-sbc 3739  df-csb 3847  df-ss 3896  df-pss 4014  df-dif 4047  df-in 4091  df-un 4151  df-nul 4279  df-if 4482  df-pw 4558  df-sn 4585  df-pr 4587  df-tp 4589  df-op 4835  df-uni 4867  df-int 4907  df-br 5103  df-opab 5167  df-mpt 5186  df-tr 5212  df-id 5545  df-eprel 5550  df-po 5558  df-so 5559  df-fr 5603  df-we 5605  df-xp 5656  df-rel 5657  df-cnv 5658  df-co 5659  df-dm 5660  df-rn 5661  df-res 5662  df-ima 5663  df-ord 6365  df-on 6366  df-suc 6368  df-iota 6494  df-fun 6540  df-fn 6541  df-f 6542  df-fo 6544  df-fv 6546  df-1o 8479  df-2o 8480  df-no 28005  df-lts 28006  df-bday 28007
This theorem is used by:  nocvxminlem  28145  addsproplem6  28365  negsproplem6  28424  mulsproplem13  28519  mulsproplem14  28520
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