Theorem List for New Foundations Explorer - 5701-5800   *Has distinct variable
 group(s)
| Type | Label | Description | 
| Statement | 
|   | 
| Theorem | fvmpt 5701* | 
Value of a function given in maps-to notation.  (Contributed by set.mm
         contributors, 17-Aug-2011.)
 | 
| ⊢ (x =
 A → B = C)   
 &   ⊢ F =
 (x ∈
 D ↦
 B)   
 &   ⊢ C ∈ V    ⇒   ⊢ (A ∈ D →
 (F ‘A) = C) | 
|   | 
| Theorem | fvmpts 5702* | 
Value of a function given in maps-to notation, using explicit class
       substitution.  (Contributed by Scott Fenton, 17-Jul-2013.)  (Revised by
       Mario Carneiro, 31-Aug-2015.)
 | 
| ⊢ F =
 (x ∈
 C ↦
 B)    ⇒   ⊢ ((A ∈ C ∧ [A /
 x]B ∈ V) → (F
 ‘A) = [A / x]B) | 
|   | 
| Theorem | fvmptd 5703* | 
Deduction version of fvmpt 5701.  (Contributed by Scott Fenton,
       18-Feb-2013.)  (Revised by Mario Carneiro, 31-Aug-2015.)
 | 
| ⊢ (φ
 → F = (x ∈ D ↦ B))   
 &   ⊢ ((φ
 ∧ x =
 A) → B = C)   
 &   ⊢ (φ
 → A ∈ D)   
 &   ⊢ (φ
 → C ∈ V)    ⇒   ⊢ (φ
 → (F ‘A) = C) | 
|   | 
| Theorem | fvmpt2i 5704* | 
Value of a function given by the "maps to" notation.  (Contributed by
       Mario Carneiro, 23-Apr-2014.)
 | 
| ⊢ F =
 (x ∈
 A ↦
 B)    ⇒   ⊢ (x ∈ A →
 (F ‘x) = ( I ‘B)) | 
|   | 
| Theorem | fvmpt2 5705* | 
Value of a function given by the "maps to" notation.  (Contributed by
       FL, 21-Jun-2010.)
 | 
| ⊢ F =
 (x ∈
 A ↦
 B)    ⇒   ⊢ ((x ∈ A ∧ B ∈ C) →
 (F ‘x) = B) | 
|   | 
| Theorem | fvmptss 5706* | 
If all the values of the mapping are subsets of a class C, then so
       is any evaluation of the mapping, even if D is not in the base set
       A.  (Contributed by
Mario Carneiro, 13-Feb-2015.)
 | 
| ⊢ F =
 (x ∈
 A ↦
 B)    ⇒   ⊢ (∀x ∈ A B ⊆ C →
 (F ‘D) ⊆ C) | 
|   | 
| Theorem | dffn5v 5707* | 
Representation of a function in terms of its values.  (Contributed by
       FL, 14-Sep-2013.)  (Revised by Mario Carneiro, 16-Dec-2013.)
 | 
| ⊢ (F Fn
 A ↔ F = (x ∈ A ↦ (F
 ‘x))) | 
|   | 
| Theorem | fnov2 5708* | 
Representation of a function in terms of its values.  (Contributed by
       Mario Carneiro, 23-Dec-2013.)
 | 
| ⊢ (F Fn
 (A × B) ↔ F =
 (x ∈
 A, y
 ∈ B
 ↦ (xFy))) | 
|   | 
| Theorem | mpt2mptx 5709* | 
Express a two-argument function as a one-argument function, or
       vice-versa.  In this version B(x) is
not assumed to be constant
       w.r.t x.  (Contributed
by Mario Carneiro, 29-Dec-2014.)
 | 
| ⊢ (z = 〈x, y〉 →
 C = D)    ⇒   ⊢ (z ∈ ∪x ∈ A ({x} ×
 B) ↦
 C) = (x ∈ A, y ∈ B ↦ D) | 
|   | 
| Theorem | mpt2mpt 5710* | 
Express a two-argument function as a one-argument function, or
       vice-versa.  (Contributed by Mario Carneiro, 17-Dec-2013.)  (Revised by
       Mario Carneiro, 29-Dec-2014.)
 | 
| ⊢ (z = 〈x, y〉 →
 C = D)    ⇒   ⊢ (z ∈ (A ×
 B) ↦
 C) = (x ∈ A, y ∈ B ↦ D) | 
|   | 
| Theorem | ovmpt4g 5711* | 
Value of a function given by the "maps to" notation.  (This is the
       operation analog of fvmpt2 5705.)  (Contributed by NM, 21-Feb-2004.)
       (Revised by Mario Carneiro, 1-Sep-2015.)
 | 
| ⊢ F =
 (x ∈
 A, y
 ∈ B
 ↦ C)    ⇒   ⊢ ((x ∈ A ∧ y ∈ B ∧ C ∈ V) →
 (xFy) = C) | 
|   | 
| Theorem | ov2gf 5712* | 
The value of an operation class abstraction.  A version of ovmpt2g 5716
       using bound-variable hypotheses.  (Contributed by NM, 17-Aug-2006.)
       (Revised by Mario Carneiro, 19-Dec-2013.)
 | 
| ⊢ ℲxA    &   ⊢ ℲyA    &   ⊢ ℲyB    &   ⊢ ℲxG    &   ⊢ ℲyS    &   ⊢ (x =
 A → R = G)   
 &   ⊢ (y =
 B → G = S)   
 &   ⊢ F =
 (x ∈
 C, y
 ∈ D
 ↦ R)    ⇒   ⊢ ((A ∈ C ∧ B ∈ D ∧ S ∈ H) →
 (AFB) = S) | 
|   | 
| Theorem | ovmpt2x 5713* | 
The value of an operation class abstraction.  Variant of ovmpt2ga 5714
       which does not require D and x to be distinct.  (Contributed by
       Jeff Madsen, 10-Jun-2010.)  (Revised by Mario Carneiro, 20-Dec-2013.)
 | 
| ⊢ ((x =
 A ∧
 y = B)
 → R = S)   
 &   ⊢ (x =
 A → D = L)   
 &   ⊢ F =
 (x ∈
 C, y
 ∈ D
 ↦ R)    ⇒   ⊢ ((A ∈ C ∧ B ∈ L ∧ S ∈ H) →
 (AFB) = S) | 
|   | 
| Theorem | ovmpt2ga 5714* | 
Value of an operation given by a maps-to rule.  Equivalent to ov2ag 5599.
       (Contributed by Mario Carneiro, 19-Dec-2013.)
 | 
| ⊢ ((x =
 A ∧
 y = B)
 → R = S)   
 &   ⊢ F =
 (x ∈
 C, y
 ∈ D
 ↦ R)    ⇒   ⊢ ((A ∈ C ∧ B ∈ D ∧ S ∈ H) →
 (AFB) = S) | 
|   | 
| Theorem | ovmpt2a 5715* | 
Value of an operation given by a maps-to rule.  Equivalent to
         ov2ag 5599.  (Contributed by set.mm contributors,
19-Dec-2013.)
 | 
| ⊢ ((x =
 A ∧
 y = B)
 → R = S)   
 &   ⊢ F =
 (x ∈
 C, y
 ∈ D
 ↦ R)   
 &   ⊢ S ∈ V    ⇒   ⊢ ((A ∈ C ∧ B ∈ D) →
 (AFB) = S) | 
|   | 
| Theorem | ovmpt2g 5716* | 
Value of an operation given by a maps-to rule.  (Unnecessary distinct
       variable restrictions were removed by David Abernethy, 19-Jun-2012.)
       (Contributed by set.mm contributors, 2-Oct-2007.)  (Revised by set.mm
       contributors, 24-Jul-2012.)
 | 
| ⊢ (x =
 A → R = G)   
 &   ⊢ (y =
 B → G = S)   
 &   ⊢ F =
 (x ∈
 C, y
 ∈ D
 ↦ R)    ⇒   ⊢ ((A ∈ C ∧ B ∈ D ∧ S ∈ H) →
 (AFB) = S) | 
|   | 
| Theorem | ovmpt2 5717* | 
Value of an operation given by a maps-to rule.  Equivalent to ov2 in
         set.mm.  (Contributed by set.mm contributors, 12-Sep-2011.)
 | 
| ⊢ (x =
 A → R = G)   
 &   ⊢ (y =
 B → G = S)   
 &   ⊢ F =
 (x ∈
 C, y
 ∈ D
 ↦ R)   
 &   ⊢ S ∈ V    ⇒   ⊢ ((A ∈ C ∧ B ∈ D) →
 (AFB) = S) | 
|   | 
| Theorem | rnmpt2 5718* | 
The range of an operation given by the "maps to" notation. 
(Contributed
       by FL, 20-Jun-2011.)
 | 
| ⊢ F =
 (x ∈
 A, y
 ∈ B
 ↦ C)    ⇒   ⊢ ran F =
 {z ∣
 ∃x
 ∈ A
 ∃y
 ∈ B
 z = C} | 
|   | 
| Theorem | mptv 5719* | 
Function with universal domain in maps-to notation.  (Contributed by
       set.mm contributors, 16-Aug-2013.)
 | 
| ⊢ (x ∈ V ↦ B) = {〈x, y〉 ∣ y = B} | 
|   | 
| Theorem | mpt2v 5720* | 
Operation with universal domain in maps-to notation.  (Contributed by
       set.mm contributors, 16-Aug-2013.)
 | 
| ⊢ (x ∈ V, y ∈ V ↦ C) = {〈〈x, y〉, z〉 ∣ z =
 C} | 
|   | 
| Theorem | mptresid 5721* | 
The restricted identity expressed with the "maps to" notation.
       (Contributed by FL, 25-Apr-2012.)
 | 
| ⊢ (x ∈ A ↦ x) = ( I
 ↾ A) | 
|   | 
| Theorem | fvmptex 5722* | 
Express a function F whose
value B may not always be a
set in
       terms of another function G for which sethood is guaranteed.  (Note
       that ( I  ‘B) is
just shorthand for
       if(B ∈ V, B, ∅), and it is always a set by fvex 5340.)  Note
       also that these functions are not the same; wherever B(C) is
not
       a set, C is not in the
domain of F (so it evaluates
to the empty
       set), but C is in the
domain of G, and G(C) is defined
       to be the empty set.  (Contributed by Mario Carneiro, 14-Jul-2013.)
       (Revised by Mario Carneiro, 23-Apr-2014.)
 | 
| ⊢ F =
 (x ∈
 A ↦
 B)   
 &   ⊢ G =
 (x ∈
 A ↦ ( I
 ‘B))    ⇒   ⊢ (F
 ‘C) = (G ‘C) | 
|   | 
| Theorem | fvmptf 5723* | 
Value of a function given by an ordered-pair class abstraction.  This
       version of fvmptg 5699 uses bound-variable hypotheses instead of
distinct
       variable conditions.  (Contributed by NM, 8-Nov-2005.)  (Revised by
       Mario Carneiro, 15-Oct-2016.)
 | 
| ⊢ ℲxA    &   ⊢ ℲxC    &   ⊢ (x =
 A → B = C)   
 &   ⊢ F =
 (x ∈
 D ↦
 B)    ⇒   ⊢ ((A ∈ D ∧ C ∈ V) →
 (F ‘A) = C) | 
|   | 
| Theorem | fvmptnf 5724* | 
The value of a function given by an ordered-pair class abstraction is
       the empty set when the class it would otherwise map to is a proper
       class.  This version of fvmptn 5725 uses bound-variable hypotheses
instead
       of distinct variable conditions.  (Contributed by NM, 21-Oct-2003.)
       (Revised by Mario Carneiro, 11-Sep-2015.)
 | 
| ⊢ ℲxA    &   ⊢ ℲxC    &   ⊢ (x =
 A → B = C)   
 &   ⊢ F =
 (x ∈
 D ↦
 B)    ⇒   ⊢ (¬ C
 ∈ V → (F ‘A) =
 ∅) | 
|   | 
| Theorem | fvmptn 5725* | 
This somewhat non-intuitive theorem tells us the value of its function
       is the empty set when the class C it would otherwise map to is a
       proper class.  This is a technical lemma that can help eliminate
       redundant sethood antecedents otherwise required by fvmptg 5699.
       (Contributed by NM, 21-Oct-2003.)  (Revised by Mario Carneiro,
       9-Sep-2013.)
 | 
| ⊢ (x =
 D → B = C)   
 &   ⊢ F =
 (x ∈
 A ↦
 B)    ⇒   ⊢ (¬ C
 ∈ V → (F ‘D) =
 ∅) | 
|   | 
| Theorem | fvmptss2 5726* | 
A mapping always evaluates to a subset of the substituted expression in
       the mapping, even if this is a proper class, or we are out of the
       domain.  (Contributed by Mario Carneiro, 13-Feb-2015.)
 | 
| ⊢ (x =
 D → B = C)   
 &   ⊢ F =
 (x ∈
 A ↦
 B)    ⇒   ⊢ (F
 ‘D) ⊆ C | 
|   | 
| Theorem | f1od 5727* | 
Describe an implicit one-to-one onto function.  (Contributed by Mario
         Carneiro, 12-May-2014.)
 | 
| ⊢ F =
 (x ∈
 A ↦
 C)   
 &   ⊢ ((φ
 ∧ x ∈ A) →
 C ∈
 W)   
 &   ⊢ ((φ
 ∧ y ∈ B) →
 D ∈
 X)   
 &   ⊢ (φ
 → ((x ∈ A ∧ y = C) ↔ (y
 ∈ B
 ∧ x =
 D)))    ⇒   ⊢ (φ
 → F:A–1-1-onto→B) | 
|   | 
| Theorem | f1o2d 5728* | 
Describe an implicit one-to-one onto function.  (Contributed by Mario
       Carneiro, 12-May-2014.)
 | 
| ⊢ F =
 (x ∈
 A ↦
 C)   
 &   ⊢ ((φ
 ∧ x ∈ A) →
 C ∈
 B)   
 &   ⊢ ((φ
 ∧ y ∈ B) →
 D ∈
 A)   
 &   ⊢ ((φ
 ∧ (x
 ∈ A
 ∧ y ∈ B)) →
 (x = D
 ↔ y = C))    ⇒   ⊢ (φ
 → F:A–1-1-onto→B) | 
|   | 
| Theorem | dfswap3 5729* | 
Alternate definition of  Swap  as an
operator abstraction.
       (Contributed by SF, 23-Feb-2015.)
 | 
| ⊢  Swap  = {〈〈x, y〉, z〉 ∣ z = 〈y, x〉} | 
|   | 
| Theorem | dfswap4 5730* | 
Alternate definition of  Swap  as an
operator mapping.  (Contributed
       by SF, 23-Feb-2015.)
 | 
| ⊢  Swap  = (x ∈ V, y ∈ V ↦ 〈y, x〉) | 
|   | 
| Theorem | fmpt2x 5731* | 
Functionality, domain and codomain of a class given by the "maps to"
       notation, where B(x) is not constant but depends on x.
       (Contributed by NM, 29-Dec-2014.)
 | 
| ⊢ F =
 (x ∈
 A, y
 ∈ B
 ↦ C)    ⇒   ⊢ (∀x ∈ A ∀y ∈ B C ∈ D ↔
 F:∪x ∈ A ({x} × B)–→D) | 
|   | 
| Theorem | fmpt2 5732* | 
Functionality, domain and range of a class given by the "maps to"
       notation.  (Contributed by FL, 17-May-2010.)
 | 
| ⊢ F =
 (x ∈
 A, y
 ∈ B
 ↦ C)    ⇒   ⊢ (∀x ∈ A ∀y ∈ B C ∈ D ↔
 F:(A
 × B)–→D) | 
|   | 
| Theorem | fnmpt2 5733* | 
Functionality and domain of a class given by the "maps to" notation.
       (Contributed by FL, 17-May-2010.)
 | 
| ⊢ F =
 (x ∈
 A, y
 ∈ B
 ↦ C)    ⇒   ⊢ (∀x ∈ A ∀y ∈ B C ∈ V →
 F Fn (A × B)) | 
|   | 
| Theorem | fnmpt2i 5734* | 
Functionality and domain of a class given by the "maps to" notation.
       (Contributed by FL, 17-May-2010.)
 | 
| ⊢ F =
 (x ∈
 A, y
 ∈ B
 ↦ C)   
 &   ⊢ C ∈ V    ⇒   ⊢ F Fn
 (A × B) | 
|   | 
| Theorem | dmmpt2 5735* | 
Domain of a class given by the "maps to" notation.  (Contributed by
FL,
       17-May-2010.)
 | 
| ⊢ F =
 (x ∈
 A, y
 ∈ B
 ↦ C)   
 &   ⊢ C ∈ V    ⇒   ⊢ dom F =
 (A × B) | 
|   | 
| 2.3.10  Set construction lemmas
 | 
|   | 
| Syntax | ctxp 5736 | 
Extend the definition of a class to include the tail cross product.
 | 
| class
 (A ⊗ B) | 
|   | 
| Definition | df-txp 5737 | 
Define the tail cross product of two classes.  Definition from [Holmes]
     p. 40.  See brtxp 5784 for membership.  (Contributed by SF,
9-Feb-2015.)
 | 
| ⊢ (A ⊗
 B) = ((◡1st ∘ A) ∩
 (◡2nd ∘ B)) | 
|   | 
| Syntax | cpprod 5738 | 
Extend the definition of a class to include the parallel product
     operation.
 | 
| class
  PProd (A, B) | 
|   | 
| Definition | df-pprod 5739 | 
Define the parallel product operation.  (Contributed by SF,
     9-Feb-2015.)
 | 
| ⊢  PProd (A, B) =
 ((A ∘
 1st ) ⊗ (B ∘ 2nd )) | 
|   | 
| Syntax | cfix 5740 | 
Extend the definition of a class to include the fixed points of a
     relationship.
 | 
| class
  Fix A | 
|   | 
| Definition | df-fix 5741 | 
Define the fixed points of a relationship.  (Contributed by SF,
     9-Feb-2015.)
 | 
| ⊢  Fix A = ran (A
 ∩ I ) | 
|   | 
| Syntax | ccup 5742 | 
Extend the definition of a class to include the cup function.
 | 
| class
  Cup | 
|   | 
| Definition | df-cup 5743* | 
Define the cup function.  (Contributed by SF, 9-Feb-2015.)
 | 
| ⊢  Cup = (x ∈ V, y ∈ V ↦ (x ∪
 y)) | 
|   | 
| Syntax | cdisj 5744 | 
Extend the definition of a class to include the disjoint relationship.
 | 
| class
  Disj | 
|   | 
| Definition | df-disj 5745* | 
Define the relationship of all disjoint sets.  (Contributed by SF,
       9-Feb-2015.)
 | 
| ⊢  Disj = {〈x, y〉 ∣ (x ∩
 y) = ∅} | 
|   | 
| Syntax | caddcfn 5746 | 
Extend the definition of a class to include the cardinal sum function.
 | 
| class
  AddC | 
|   | 
| Definition | df-addcfn 5747* | 
Define the function representing cardinal sum.  (Contributed by SF,
       9-Feb-2015.)
 | 
| ⊢  AddC = (x ∈ V, y ∈ V ↦ (x
 +c y)) | 
|   | 
| Syntax | ccompose 5748 | 
Extend the definition of a class to include the compostion function.
 | 
| class
  Compose | 
|   | 
| Definition | df-compose 5749* | 
Define the composition function.  (Contributed by Scott Fenton,
       19-Apr-2021.)
 | 
| ⊢  Compose =
 (x ∈ V,
 y ∈ V
 ↦ (x
 ∘ y)) | 
|   | 
| Syntax | cins2 5750 | 
Extend the definition of a class to include the second insertion
     operation.
 | 
| class
  Ins2 A | 
|   | 
| Definition | df-ins2 5751 | 
Define the second insertion operation.  (Contributed by SF,
     9-Feb-2015.)
 | 
| ⊢  Ins2 A = (V ⊗ A) | 
|   | 
| Syntax | cins3 5752 | 
Extend the definition of a class to include the third insertion
     operation.
 | 
| class
  Ins3 A | 
|   | 
| Definition | df-ins3 5753 | 
Define the third insertion operation.  (Contributed by SF, 9-Feb-2015.)
 | 
| ⊢  Ins3 A = (A ⊗
 V) | 
|   | 
| Syntax | cimage 5754 | 
Extend the definition of a class to include the image function.
 | 
| class
 ImageA | 
|   | 
| Definition | df-image 5755 | 
Define the image function of a class.  (Contributed by SF, 9-Feb-2015.)
     (Revised by Scott Fenton, 19-Apr-2021.)
 | 
| ⊢ ImageA =
 ∼ (( Ins2  S 
 ⊕ Ins3 ( S 
 ∘ ◡ SI A)) “ 1c) | 
|   | 
| Syntax | cins4 5756 | 
Extend the definition of a class to include the fourth insertion
     operation.
 | 
| class
  Ins4 A | 
|   | 
| Definition | df-ins4 5757 | 
Define the fourth insertion operation.  (Contributed by SF,
     9-Feb-2015.)
 | 
| ⊢  Ins4 A = (◡(1st ⊗ ((1st
 ∘ 2nd ) ⊗
 ((1st ∘ 2nd ) ∘ 2nd ))) “ A) | 
|   | 
| Syntax | csi3 5758 | 
Extend the definition of a class to include the triple singleton image.
 | 
| class
  SI3 A | 
|   | 
| Definition | df-si3 5759 | 
Define the triple singleton image.  (Contributed by SF, 9-Feb-2015.)
 | 
| ⊢  SI3 A = (( SI
 1st ⊗ ( SI
 (1st ∘ 2nd )
 ⊗  SI (2nd ∘ 2nd ))) “ ℘1A) | 
|   | 
| Syntax | cfuns 5760 | 
Extend the definition of a class to include the set of all functions.
 | 
| class
  Funs | 
|   | 
| Definition | df-funs 5761 | 
Define the class of all functions.  (Contributed by SF, 9-Feb-2015.)
 | 
| ⊢  Funs = {f ∣ Fun f} | 
|   | 
| Syntax | cfns 5762 | 
Extend the definition of a class to include the function with domain
     relationship.
 | 
| class
  Fns | 
|   | 
| Definition | df-fns 5763* | 
Define the function with domain relationship.  (Contributed by SF,
       9-Feb-2015.)
 | 
| ⊢  Fns = {〈f, a〉 ∣ f Fn
 a} | 
|   | 
| Syntax | ccross 5764 | 
Extend the definition of a class to include the cross product function.
 | 
| class
  Cross | 
|   | 
| Definition | df-cross 5765* | 
Define the cross product function.  (Contributed by SF, 9-Feb-2015.)
 | 
| ⊢  Cross = (x ∈ V, y ∈ V ↦ (x ×
 y)) | 
|   | 
| Syntax | cpw1fn 5766 | 
Extend the definition of a class to include the unit power class
     function.
 | 
| class
  Pw1Fn | 
|   | 
| Definition | df-pw1fn 5767 | 
Define the function that takes a singleton to the unit power class of its
     member.  This function is defined in such a way as to ensure
     stratification.  (Contributed by SF, 9-Feb-2015.)
 | 
| ⊢  Pw1Fn = (x ∈
 1c ↦ ℘1∪x) | 
|   | 
| Syntax | cfullfun 5768 | 
Extend the definition of a class to include the full function
     operation.
 | 
| class
  FullFun F | 
|   | 
| Definition | df-fullfun 5769 | 
Define the full function operator.  This is a function over V
that
     agrees with the function value of F at every point.  (Contributed by
     SF, 9-Feb-2015.)
 | 
| ⊢  FullFun F = ((( I ∘
 F) ∖ (
 ∼ I ∘ F)) ∪ ( ∼ dom (( I ∘ F) ∖ ( ∼ I ∘
 F)) × {∅})) | 
|   | 
| Syntax | cdomfn 5770 | 
Extend the definition of a class to include the domain function.
 | 
| class
  Dom | 
|   | 
| Definition | df-domfn 5771 | 
Define the domain function.  This is a function wrapper for the domain
     operator.  (Contributed by Scott Fenton, 9-Aug-2019.)
 | 
| ⊢  Dom = (x ∈ V ↦ dom x) | 
|   | 
| Syntax | cranfn 5772 | 
Extend the definition of a class to include the range function.
 | 
| class
  Ran | 
|   | 
| Definition | df-ranfn 5773 | 
Define the range function.  This is a function wrapper for the range
     operator.  (Contributed by Scott Fenton, 9-Aug-2019.)
 | 
| ⊢  Ran = (x ∈ V ↦ ran x) | 
|   | 
| Theorem | brsnsi 5774 | 
Binary relationship of singletons in a singleton image.  (Contributed by
       SF, 9-Feb-2015.)
 | 
| ⊢ A ∈ V   
 &   ⊢ B ∈ V    ⇒   ⊢ ({A} SI R{B} ↔ ARB) | 
|   | 
| Theorem | opsnelsi 5775 | 
Ordered pair membership of singletons in a singleton image.
       (Contributed by SF, 9-Feb-2015.)
 | 
| ⊢ A ∈ V   
 &   ⊢ B ∈ V    ⇒   ⊢ (〈{A}, {B}〉 ∈  SI R ↔ 〈A, B〉 ∈ R) | 
|   | 
| Theorem | brsnsi1 5776* | 
Binary relationship of a singleton to an arbitrary set in a singleton
       image.  (Contributed by SF, 9-Mar-2015.)
 | 
| ⊢ A ∈ V    ⇒   ⊢ ({A} SI RB ↔ ∃x(B = {x} ∧ ARx)) | 
|   | 
| Theorem | brsnsi2 5777* | 
Binary relationship of an arbitrary set to a singleton in a singleton
       image.  (Contributed by SF, 9-Mar-2015.)
 | 
| ⊢ A ∈ V    ⇒   ⊢ (B SI R{A} ↔ ∃x(B = {x} ∧ xRA)) | 
|   | 
| Theorem | brco1st 5778 | 
Binary relationship of composition with 1st. 
(Contributed by SF,
       9-Feb-2015.)
 | 
| ⊢ A ∈ V   
 &   ⊢ B ∈ V    ⇒   ⊢ (〈A, B〉(R ∘ 1st )C ↔ ARC) | 
|   | 
| Theorem | brco2nd 5779 | 
Binary relationship of composition with 2nd. 
(Contributed by SF,
       9-Feb-2015.)
 | 
| ⊢ A ∈ V   
 &   ⊢ B ∈ V    ⇒   ⊢ (〈A, B〉(R ∘ 2nd )C ↔ BRC) | 
|   | 
| Theorem | txpeq1 5780 | 
Equality theorem for tail cross product.  (Contributed by Scott Fenton,
     31-Jul-2019.)
 | 
| ⊢ (A =
 B → (A ⊗ C) =
 (B ⊗ C)) | 
|   | 
| Theorem | txpeq2 5781 | 
Equality theorem for tail cross product.  (Contributed by Scott Fenton,
     31-Jul-2019.)
 | 
| ⊢ (A =
 B → (C ⊗ A) =
 (C ⊗ B)) | 
|   | 
| Theorem | trtxp 5782 | 
Trinary relationship over a tail cross product.  (Contributed by SF,
       13-Feb-2015.)
 | 
| ⊢ (A(R ⊗ S)〈B, C〉 ↔ (ARB ∧ ASC)) | 
|   | 
| Theorem | oteltxp 5783 | 
Ordered triple membership in a tail cross product.  (Contributed by SF,
     13-Feb-2015.)
 | 
| ⊢ (〈A, 〈B, C〉〉 ∈ (R ⊗
 S) ↔ (〈A, B〉 ∈ R ∧ 〈A, C〉 ∈ S)) | 
|   | 
| Theorem | brtxp 5784* | 
Binary relationship over a tail cross product.  (Contributed by SF,
       11-Feb-2015.)
 | 
| ⊢ (A(R ⊗ S)B ↔
 ∃x∃y(B = 〈x, y〉 ∧ ARx ∧ ASy)) | 
|   | 
| Theorem | txpexg 5785 | 
The tail cross product of two sets is a set.  (Contributed by SF,
     9-Feb-2015.)
 | 
| ⊢ ((A ∈ V ∧ B ∈ W) →
 (A ⊗ B) ∈
 V) | 
|   | 
| Theorem | txpex 5786 | 
The tail cross product of two sets is a set.  (Contributed by SF,
       9-Feb-2015.)
 | 
| ⊢ A ∈ V   
 &   ⊢ B ∈ V    ⇒   ⊢ (A ⊗
 B) ∈
 V | 
|   | 
| Theorem | restxp 5787 | 
Restriction distributes over tail cross product.  (Contributed by SF,
       24-Feb-2015.)
 | 
| ⊢ ((A
 ⊗ B) ↾ C) =
 ((A ↾
 C) ⊗ (B ↾ C)) | 
|   | 
| Theorem | elfix 5788 | 
Membership in the fixed points of a relationship.  (Contributed by SF,
       11-Feb-2015.)
 | 
| ⊢ (A ∈  Fix R ↔ ARA) | 
|   | 
| Theorem | fixexg 5789 | 
The fixed points of a set form a set.  (Contributed by SF,
     11-Feb-2015.)
 | 
| ⊢ (R ∈ V →
  Fix R ∈ V) | 
|   | 
| Theorem | fixex 5790 | 
The fixed points of a set form a set.  (Contributed by SF,
       11-Feb-2015.)
 | 
| ⊢ R ∈ V    ⇒   ⊢  Fix R ∈
 V | 
|   | 
| Theorem | op1st2nd 5791 | 
Express equality to an ordered pair via 1st and 2nd.
       (Contributed by SF, 12-Feb-2015.)
 | 
| ⊢ A ∈ V   
 &   ⊢ B ∈ V    ⇒   ⊢ ((C1st A ∧ C2nd B) ↔ C =
 〈A,
 B〉) | 
|   | 
| Theorem | otelins2 5792 | 
Ordered triple membership in Ins2. 
(Contributed by SF,
       13-Feb-2015.)
 | 
| ⊢ B ∈ V    ⇒   ⊢ (〈A, 〈B, C〉〉 ∈ Ins2 R ↔ 〈A, C〉 ∈ R) | 
|   | 
| Theorem | otelins3 5793 | 
Ordered triple membership in Ins3. 
(Contributed by SF,
       13-Feb-2015.)
 | 
| ⊢ C ∈ V    ⇒   ⊢ (〈A, 〈B, C〉〉 ∈ Ins3 R ↔ 〈A, B〉 ∈ R) | 
|   | 
| Theorem | brimage 5794 | 
Binary relationship over the image function.  (Contributed by SF,
       11-Feb-2015.)
 | 
| ⊢ A ∈ V   
 &   ⊢ B ∈ V    ⇒   ⊢ (AImageRB ↔ B =
 (R “ A)) | 
|   | 
| Theorem | oqelins4 5795 | 
Ordered quadruple membership in Ins4.  (Contributed by SF,
       13-Feb-2015.)
 | 
| ⊢ D ∈ V    ⇒   ⊢ (〈A, 〈B, 〈C, D〉〉〉 ∈ Ins4 R ↔ 〈A, 〈B, C〉〉 ∈ R) | 
|   | 
| Theorem | ins2exg 5796 | 
Ins2 preserves sethood. 
(Contributed by SF, 9-Mar-2015.)
 | 
| ⊢ (A ∈ V →
 Ins2 A ∈ V) | 
|   | 
| Theorem | ins3exg 5797 | 
Ins3 preserves sethood. 
(Contributed by SF, 22-Feb-2015.)
 | 
| ⊢ (A ∈ V →
 Ins3 A ∈ V) | 
|   | 
| Theorem | ins2ex 5798 | 
Ins2 preserves sethood. 
(Contributed by SF, 12-Feb-2015.)
 | 
| ⊢ A ∈ V    ⇒   ⊢  Ins2 A ∈
 V | 
|   | 
| Theorem | ins3ex 5799 | 
Ins3 preserves sethood. 
(Contributed by SF, 12-Feb-2015.)
 | 
| ⊢ A ∈ V    ⇒   ⊢  Ins3 A ∈
 V | 
|   | 
| Theorem | ins4ex 5800 | 
Ins4 preserves sethood. 
(Contributed by SF, 12-Feb-2015.)
 | 
| ⊢ A ∈ V    ⇒   ⊢  Ins4 A ∈
 V |