Theorem moexexvw 2653

Description: "At most one" double quantification. Version of moexexv 2664 with an additional disjoint variable condition, which does not require ax-13 2401. (Contributed by NM, 26-Jan-1997.) (Revised by GG, 22-Aug-2023.) Factor out common proof lines with moexex 2663. (Revised by Wolf Lammen, 2-Oct-2023.)

Assertion

Ref	Expression
moexexvw	⊢ ((∃*𝑥𝜑 ∧ ∀𝑥∃*𝑦𝜓) → ∃*𝑦∃𝑥(𝜑 ∧ 𝜓))

Distinct variable groups:   𝑥,𝑦   𝜑,𝑦

Allowed substitution hints:   𝜑(𝑥)   𝜓(𝑥, 𝑦)

Proof of Theorem moexexvw

Step	Hyp	Ref	Expression
1		nfv 1946	. 2 ⊢ Ⅎ𝑦𝜑
2		nfv 1946	. 2 ⊢ Ⅎ𝑦∃*𝑥𝜑
3		nfe1 2186	. . 3 ⊢ Ⅎ𝑥∃𝑥(𝜑 ∧ 𝜓)
4	3	nfmov 2585	. 2 ⊢ Ⅎ𝑥∃*𝑦∃𝑥(𝜑 ∧ 𝜓)
5	1, 2, 4	moexexlem 2651	1 ⊢ ((∃*𝑥𝜑 ∧ ∀𝑥∃*𝑦𝜓) → ∃*𝑦∃𝑥(𝜑 ∧ 𝜓))

This proof depends on syntax axioms:   → wi 4   ∧ wa 401  ∀wal 1567  ∃wex 1811  ∃*wmo 2562

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-10 2177  ax-11 2193  ax-12 2212

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-tru 1572  df-ex 1812  df-nf 1816  df-mo 2564

This theorem is used by:  mosub  3670  funco  6580  tfsconcatlem  44338