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Theorem rdgsucopabn 3942
Description: The value of the recursive definition generator at a successor (special case where the characteristic function is an ordered-pair class abstraction and where the mapping class D is a proper class). This is a technical lemma that can be used together with rdgsucopab 3941 to help eliminate redundant sethood antecedents.
Hypotheses
Ref Expression
rdgsucopab.1 (zA → ∀x zA)
rdgsucopab.2 (zB → ∀x zB)
rdgsucopab.3 (zD → ∀x zD)
rdgsucopab.4 F = rec({⟨x, y⟩∣y = C}, A)
rdgsucopab.5 (x = (FB) → C = D)
Assertion
Ref Expression
rdgsucopabn DV → (F ‘suc B) = ∅)
Distinct variable groups:   z,D   y,z,C   z,A   z,B   x,y,z

Proof of Theorem rdgsucopabn
StepHypRef Expression
1 rdgsuct 3940 . . . . 5 (B ∈ On → (rec({⟨x, y⟩∣y = C}, A) ‘suc B) = ({⟨x, y⟩∣y = C} ‘(rec({⟨x, y⟩∣y = C}, A) ‘B)))
2 rdgsucopab.4 . . . . . 6 F = rec({⟨x, y⟩∣y = C}, A)
32fveq1i 3720 . . . . 5 (F ‘suc B) = (rec({⟨x, y⟩∣y = C}, A) ‘suc B)
41, 3syl5eq 1517 . . . 4 (B ∈ On → (F ‘suc B) = ({⟨x, y⟩∣y = C} ‘(rec({⟨x, y⟩∣y = C}, A) ‘B)))
5 hbopab1 2809 . . . . . . 7 (z ∈ {⟨x, y⟩∣y = C} → ∀x z ∈ {⟨x, y⟩∣y = C})
6 rdgsucopab.1 . . . . . . 7 (zA → ∀x zA)
75, 6hbrdg 3931 . . . . . 6 (z ∈ rec({⟨x, y⟩∣y = C}, A) → ∀x z ∈ rec({⟨x, y⟩∣y = C}, A))
8 rdgsucopab.2 . . . . . 6 (zB → ∀x zB)
97, 8hbfv 3724 . . . . 5 (z ∈ (rec({⟨x, y⟩∣y = C}, A) ‘B) → ∀x z ∈ (rec({⟨x, y⟩∣y = C}, A) ‘B))
10 rdgsucopab.3 . . . . 5 (zD → ∀x zD)
112fveq1i 3720 . . . . . . 7 (FB) = (rec({⟨x, y⟩∣y = C}, A) ‘B)
1211eqeq2i 1483 . . . . . 6 (x = (FB) ↔ x = (rec({⟨x, y⟩∣y = C}, A) ‘B))
13 rdgsucopab.5 . . . . . 6 (x = (FB) → C = D)
1412, 13sylbir 201 . . . . 5 (x = (rec({⟨x, y⟩∣y = C}, A) ‘B) → C = D)
159, 10, 14fvopabnf 3783 . . . 4 DV → ({⟨x, y⟩∣y = C} ‘(rec({⟨x, y⟩∣y = C}, A) ‘B)) = ∅)
164, 15sylan9eq 1525 . . 3 ((B ∈ On ⋀ ¬ DV) → (F ‘suc B) = ∅)
1716ex 373 . 2 (B ∈ On → (¬ DV → (F ‘suc B) = ∅))
18 sucelon 3064 . . . . . 6 (B ∈ On ↔ suc B ∈ On)
192dmeqi 3308 . . . . . . . 8 dom F = dom rec({⟨x, y⟩∣y = C}, A)
20 rdgfnon 3934 . . . . . . . . 9 rec({⟨x, y⟩∣y = C}, A) Fn On
21 fndm 3583 . . . . . . . . 9 (rec({⟨x, y⟩∣y = C}, A) Fn On → dom rec({⟨x, y⟩∣y = C}, A) = On)
2220, 21ax-mp 7 . . . . . . . 8 dom rec({⟨x, y⟩∣y = C}, A) = On
2319, 22eqtr 1493 . . . . . . 7 dom F = On
2423eleq2i 1536 . . . . . 6 (suc B ∈ dom F ↔ suc B ∈ On)
2518, 24bitr4 176 . . . . 5 (B ∈ On ↔ suc B ∈ dom F)
2625negbii 187 . . . 4 B ∈ On ↔ ¬ suc B ∈ dom F)
27 ndmfv 3740 . . . 4 (¬ suc B ∈ dom F → (F ‘suc B) = ∅)
2826, 27sylbi 199 . . 3 B ∈ On → (F ‘suc B) = ∅)
2928a1d 12 . 2 B ∈ On → (¬ DV → (F ‘suc B) = ∅))
3017, 29pm2.61i 126 1 DV → (F ‘suc B) = ∅)
Colors of variables: wff set class
Syntax hints:  ¬ wn 2   → wi 3  ∀wal 953   = wceq 955   ∈ wcel 957  Vcvv 1808  ∅c0 2277  {copab 2662  Oncon0 2944  suc csuc 2946  dom cdm 3166   Fn wfn 3173   ‘cfv 3178  reccrdg 3926
This theorem is referenced by:  alephon 4848
This theorem was proved from axioms:  ax-1 4  ax-2 5  ax-3 6  ax-mp 7  ax-7 961  ax-gen 962  ax-8 963  ax-9 964  ax-10 965  ax-11 966  ax-12 967  ax-13 968  ax-14 969  ax-17 970  ax-4 972  ax-5o 974  ax-6o 977  ax-9o 1122  ax-10o 1139  ax-16 1209  ax-11o 1217  ax-ext 1458  ax-rep 2689  ax-sep 2699  ax-nul 2706  ax-pow 2738  ax-pr 2775  ax-un 2862
This theorem depends on definitions:  df-bi 147  df-or 224  df-an 225  df-3or 775  df-3an 776  df-ex 980  df-sb 1171  df-eu 1381  df-mo 1382  df-clab 1463  df-cleq 1468  df-clel 1471  df-ne 1585  df-ral 1647  df-rex 1648  df-rab 1650  df-v 1809  df-sbc 1939  df-dif 2046  df-un 2047  df-in 2048  df-ss 2050  df-nul 2278  df-if 2359  df-pw 2399  df-sn 2409  df-pr 2410  df-tp 2412  df-op 2413  df-uni 2500  df-iun 2564  df-br 2616  df-opab 2663  df-tr 2677  df-eprel 2828  df-id 2831  df-po 2836  df-so 2846  df-fr 2913  df-we 2930  df-ord 2947  df-on 2948  df-lim 2949  df-suc 2950  df-xp 3180  df-rel 3181  df-cnv 3182  df-co 3183  df-dm 3184  df-rn 3185  df-res 3186  df-ima 3187  df-fun 3188  df-fn 3189  df-fv 3194  df-rdg 3927
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