Theorem ackvalsucsucval 49893

Description: The Ackermann function at the successors. This is the third equation of Péter's definition of the Ackermann function. (Contributed by AV, 8-May-2024.)

Assertion

Ref	Expression
ackvalsucsucval	⊢ ((𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) → ((Ack‘(𝑀 + 1))‘(𝑁 + 1)) = ((Ack‘𝑀)‘((Ack‘(𝑀 + 1))‘𝑁)))

Proof of Theorem ackvalsucsucval

Step	Hyp	Ref	Expression
1		peano2nn0 12649	. . 3 ⊢ (𝑁 ∈ ℕ0 → (𝑁 + 1) ∈ ℕ0)
2		ackvalsuc1 49884	. . 3 ⊢ ((𝑀 ∈ ℕ0 ∧ (𝑁 + 1) ∈ ℕ0) → ((Ack‘(𝑀 + 1))‘(𝑁 + 1)) = (((IterComp‘(Ack‘𝑀))‘((𝑁 + 1) + 1))‘1))
3	1, 2	sylan2 605	. 2 ⊢ ((𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) → ((Ack‘(𝑀 + 1))‘(𝑁 + 1)) = (((IterComp‘(Ack‘𝑀))‘((𝑁 + 1) + 1))‘1))
4		fvexd 6900	. . . . 5 ⊢ ((𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) → (Ack‘𝑀) ∈ V)
5	1	adantl 487	. . . . 5 ⊢ ((𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) → (𝑁 + 1) ∈ ℕ0)
6		eqidd 2761	. . . . 5 ⊢ ((𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) → ((IterComp‘(Ack‘𝑀))‘(𝑁 + 1)) = ((IterComp‘(Ack‘𝑀))‘(𝑁 + 1)))
7		itcovalsucov 49873	. . . . 5 ⊢ (((Ack‘𝑀) ∈ V ∧ (𝑁 + 1) ∈ ℕ0 ∧ ((IterComp‘(Ack‘𝑀))‘(𝑁 + 1)) = ((IterComp‘(Ack‘𝑀))‘(𝑁 + 1))) → ((IterComp‘(Ack‘𝑀))‘((𝑁 + 1) + 1)) = ((Ack‘𝑀) ∘ ((IterComp‘(Ack‘𝑀))‘(𝑁 + 1))))
8	4, 5, 6, 7	syl3anc 1398	. . . 4 ⊢ ((𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) → ((IterComp‘(Ack‘𝑀))‘((𝑁 + 1) + 1)) = ((Ack‘𝑀) ∘ ((IterComp‘(Ack‘𝑀))‘(𝑁 + 1))))
9	8	fveq1d 6887	. . 3 ⊢ ((𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) → (((IterComp‘(Ack‘𝑀))‘((𝑁 + 1) + 1))‘1) = (((Ack‘𝑀) ∘ ((IterComp‘(Ack‘𝑀))‘(𝑁 + 1)))‘1))
10		ackfnnn0 49890	. . . . . . 7 ⊢ (𝑀 ∈ ℕ0 → (Ack‘𝑀) Fn ℕ0)
11	10	adantr 486	. . . . . 6 ⊢ ((𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) → (Ack‘𝑀) Fn ℕ0)
12		nn0ex 12615	. . . . . . . . 9 ⊢ ℕ0 ∈ V
13	12	a1i 11	. . . . . . . 8 ⊢ ((𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) → ℕ0 ∈ V)
14		ackendofnn0 49889	. . . . . . . . 9 ⊢ (𝑀 ∈ ℕ0 → (Ack‘𝑀):ℕ0⟶ℕ0)
15	14	adantr 486	. . . . . . . 8 ⊢ ((𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) → (Ack‘𝑀):ℕ0⟶ℕ0)
16		simpr 490	. . . . . . . 8 ⊢ ((𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) → 𝑁 ∈ ℕ0)
17	13, 15, 16	itcovalendof 49874	. . . . . . 7 ⊢ ((𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) → ((IterComp‘(Ack‘𝑀))‘𝑁):ℕ0⟶ℕ0)
18	17	ffnd 6710	. . . . . 6 ⊢ ((𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) → ((IterComp‘(Ack‘𝑀))‘𝑁) Fn ℕ0)
19	17	frnd 6718	. . . . . 6 ⊢ ((𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) → ran ((IterComp‘(Ack‘𝑀))‘𝑁) ⊆ ℕ0)
20		fnco 6657	. . . . . 6 ⊢ (((Ack‘𝑀) Fn ℕ0 ∧ ((IterComp‘(Ack‘𝑀))‘𝑁) Fn ℕ0 ∧ ran ((IterComp‘(Ack‘𝑀))‘𝑁) ⊆ ℕ0) → ((Ack‘𝑀) ∘ ((IterComp‘(Ack‘𝑀))‘𝑁)) Fn ℕ0)
21	11, 18, 19, 20	syl3anc 1398	. . . . 5 ⊢ ((𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) → ((Ack‘𝑀) ∘ ((IterComp‘(Ack‘𝑀))‘𝑁)) Fn ℕ0)
22		eqidd 2761	. . . . . . 7 ⊢ ((𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) → ((IterComp‘(Ack‘𝑀))‘𝑁) = ((IterComp‘(Ack‘𝑀))‘𝑁))
23		itcovalsucov 49873	. . . . . . 7 ⊢ (((Ack‘𝑀) ∈ V ∧ 𝑁 ∈ ℕ0 ∧ ((IterComp‘(Ack‘𝑀))‘𝑁) = ((IterComp‘(Ack‘𝑀))‘𝑁)) → ((IterComp‘(Ack‘𝑀))‘(𝑁 + 1)) = ((Ack‘𝑀) ∘ ((IterComp‘(Ack‘𝑀))‘𝑁)))
24	4, 16, 22, 23	syl3anc 1398	. . . . . 6 ⊢ ((𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) → ((IterComp‘(Ack‘𝑀))‘(𝑁 + 1)) = ((Ack‘𝑀) ∘ ((IterComp‘(Ack‘𝑀))‘𝑁)))
25	24	fneq1d 6632	. . . . 5 ⊢ ((𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) → (((IterComp‘(Ack‘𝑀))‘(𝑁 + 1)) Fn ℕ0 ↔ ((Ack‘𝑀) ∘ ((IterComp‘(Ack‘𝑀))‘𝑁)) Fn ℕ0))
26	21, 25	mpbird 260	. . . 4 ⊢ ((𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) → ((IterComp‘(Ack‘𝑀))‘(𝑁 + 1)) Fn ℕ0)
27		1nn0 12625	. . . 4 ⊢ 1 ∈ ℕ0
28		fvco2 6982	. . . 4 ⊢ ((((IterComp‘(Ack‘𝑀))‘(𝑁 + 1)) Fn ℕ0 ∧ 1 ∈ ℕ0) → (((Ack‘𝑀) ∘ ((IterComp‘(Ack‘𝑀))‘(𝑁 + 1)))‘1) = ((Ack‘𝑀)‘(((IterComp‘(Ack‘𝑀))‘(𝑁 + 1))‘1)))
29	26, 27, 28	sylancl 598	. . 3 ⊢ ((𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) → (((Ack‘𝑀) ∘ ((IterComp‘(Ack‘𝑀))‘(𝑁 + 1)))‘1) = ((Ack‘𝑀)‘(((IterComp‘(Ack‘𝑀))‘(𝑁 + 1))‘1)))
30	9, 29	eqtrd 2795	. 2 ⊢ ((𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) → (((IterComp‘(Ack‘𝑀))‘((𝑁 + 1) + 1))‘1) = ((Ack‘𝑀)‘(((IterComp‘(Ack‘𝑀))‘(𝑁 + 1))‘1)))
31		ackvalsuc1 49884	. . . 4 ⊢ ((𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) → ((Ack‘(𝑀 + 1))‘𝑁) = (((IterComp‘(Ack‘𝑀))‘(𝑁 + 1))‘1))
32	31	eqcomd 2766	. . 3 ⊢ ((𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) → (((IterComp‘(Ack‘𝑀))‘(𝑁 + 1))‘1) = ((Ack‘(𝑀 + 1))‘𝑁))
33	32	fveq2d 6889	. 2 ⊢ ((𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) → ((Ack‘𝑀)‘(((IterComp‘(Ack‘𝑀))‘(𝑁 + 1))‘1)) = ((Ack‘𝑀)‘((Ack‘(𝑀 + 1))‘𝑁)))
34	3, 30, 33	3eqtrd 2799	1 ⊢ ((𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) → ((Ack‘(𝑀 + 1))‘(𝑁 + 1)) = ((Ack‘𝑀)‘((Ack‘(𝑀 + 1))‘𝑁)))

This proof depends on syntax axioms:   → wi 4   ∧ wa 401   = wceq 1569   ∈ wcel 2144  Vcvv 3450   ⊆ wss 3895  ran crn 5651   ∘ ccom 5654   Fn wfn 6533  ⟶wf 6534  ‘cfv 6538  (class class class)co 7420  1c1 11204   + caddc 11206  ℕ₀cn0 12609  IterCompcitco 49862  Ackcack 49863

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-rep 5231  ax-sep 5248  ax-nul 5259  ax-pow 5326  ax-pr 5390  ax-un 7751  ax-inf2 9645  ax-cnex 11259  ax-resscn 11260  ax-1cn 11261  ax-icn 11262  ax-addcl 11263  ax-addrcl 11264  ax-mulcl 11265  ax-mulrcl 11266  ax-mulcom 11267  ax-addass 11268  ax-mulass 11269  ax-distr 11270  ax-i2m1 11271  ax-1ne0 11272  ax-1rid 11273  ax-rnegex 11274  ax-rrecex 11275  ax-cnre 11276  ax-pre-lttri 11277  ax-pre-lttrn 11278  ax-pre-ltadd 11279  ax-pre-mulgt0 11280

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-nel 3062  df-ral 3077  df-rex 3087  df-reu 3366  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-op 4835  df-uni 4867  df-iun 4952  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-pred 6304  df-ord 6365  df-on 6366  df-lim 6367  df-suc 6368  df-iota 6494  df-fun 6540  df-fn 6541  df-f 6542  df-f1 6543  df-fo 6544  df-f1o 6545  df-fv 6546  df-riota 7377  df-ov 7423  df-oprab 7424  df-mpo 7425  df-om 7878  df-2nd 8002  df-frecs 8302  df-wrecs 8333  df-recs 8382  df-rdg 8421  df-er 8720  df-en 8977  df-dom 8978  df-sdom 8979  df-pnf 11348  df-mnf 11349  df-xr 11350  df-ltxr 11351  df-le 11352  df-sub 11546  df-neg 11547  df-nn 12339  df-n0 12610  df-z 12697  df-uz 12969  df-seq 14148  df-itco 49864  df-ack 49865

This theorem is used by:  ackval41a  49899  ackval42  49901