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List of Syntax, Axioms (ax-) and Definitions (df-)
RefExpression (see link for any distinct variable requirements)
wn 3wff ¬ φ
wi 4wff (φψ)
ax-mp 5φ    &   (φψ)       ψ
ax-1 6(φ → (ψφ))
ax-2 7((φ → (ψχ)) → ((φψ) → (φχ)))
ax-3 8((¬ φ → ¬ ψ) → (ψφ))
wb 176wff (φψ)
df-bi 177 ¬ (((φψ) → ¬ ((φψ) → ¬ (ψφ))) → ¬ (¬ ((φψ) → ¬ (ψφ)) → (φψ)))
wo 357wff (φ ψ)
wa 358wff (φ ψ)
df-or 359((φ ψ) ↔ (¬ φψ))
df-an 360((φ ψ) ↔ ¬ (φ → ¬ ψ))
w3o 933wff (φ ψ χ)
w3a 934wff (φ ψ χ)
df-3or 935((φ ψ χ) ↔ ((φ ψ) χ))
df-3an 936((φ ψ χ) ↔ ((φ ψ) χ))
wnan 1287wff (φ ψ)
df-nan 1288((φ ψ) ↔ ¬ (φ ψ))
wxo 1304wff (φψ)
df-xor 1305((φψ) ↔ ¬ (φψ))
wtru 1316wff
wfal 1317wff
df-tru 1319( ⊤ ↔ (φφ))
df-fal 1320( ⊥ ↔ ¬ ⊤ )
whad 1378wff hadd(φ, ψ, χ)
wcad 1379wff cadd(φ, ψ, χ)
df-had 1380(hadd(φ, ψ, χ) ↔ ((φψ) ⊻ χ))
df-cad 1381(cadd(φ, ψ, χ) ↔ ((φ ψ) (χ (φψ))))
ax-meredith 1406(((((φψ) → (¬ χ → ¬ θ)) → χ) → τ) → ((τφ) → (θφ)))
wal 1540wff xφ
wex 1541wff xφ
df-ex 1542(xφ ↔ ¬ x ¬ φ)
wnf 1544wff xφ
df-nf 1545(Ⅎxφx(φxφ))
ax-gen 1546φ       xφ
ax-5 1557(x(φψ) → (xφxψ))
ax-17 1616(φxφ)
cv 1641class x
wceq 1642wff A = B
wsb 1648wff [y / x]φ
df-sb 1649([y / x]φ ↔ ((x = yφ) x(x = y φ)))
ax-9 1654 ¬ x ¬ x = y
ax-8 1675(x = y → (x = zy = z))
wcel 1710wff A B
ax-13 1712(x = y → (x zy z))
ax-14 1714(x = y → (z xz y))
ax-6 1729xφx ¬ xφ)
ax-7 1734(xyφyxφ)
ax-11 1746(x = y → (yφx(x = yφ)))
ax-12 1925x = y → (y = zx y = z))
ax-4 2135(xφφ)
ax-5o 2136(x(xφψ) → (xφxψ))
ax-6o 2137x ¬ xφφ)
ax-9o 2138(x(x = yxφ) → φ)
ax-10o 2139(x x = y → (xφyφ))
ax-10 2140(x x = yy y = x)
ax-11o 2141x x = y → (x = y → (φx(x = yφ))))
ax-12o 2142z z = x → (¬ z z = y → (x = yz x = y)))
ax-15 2143z z = x → (¬ z z = y → (x yz x y)))
ax-16 2144(x x = y → (φxφ))
weu 2204wff ∃!xφ
wmo 2205wff ∃*xφ
df-eu 2208(∃!xφyx(φx = y))
df-mo 2209(∃*xφ ↔ (xφ∃!xφ))
ax-7d 2295(xyφyxφ)
ax-8d 2296(x = y → (x = zy = z))
ax-9d1 2297 ¬ x ¬ x = x
ax-9d2 2298 ¬ x ¬ x = y
ax-10d 2299(x x = yy y = x)
ax-11d 2300(x = y → (yφx(x = yφ)))
ax-ext 2334(z(z xz y) → x = y)
cab 2339class {x φ}
df-clab 2340(x {y φ} ↔ [x / y]φ)
df-cleq 2346(x(x yx z) → y = z)       (A = Bx(x Ax B))
df-clel 2349(A Bx(x = A x B))
wnfc 2476wff xA
df-nfc 2478(xAyx y A)
wne 2516wff AB
wnel 2517wff A B
df-ne 2518(AB ↔ ¬ A = B)
df-nel 2519(A B ↔ ¬ A B)
wral 2614wff x A φ
wrex 2615wff x A φ
wreu 2616wff ∃!x A φ
wrmo 2617wff ∃*x A φ
crab 2618class {x A φ}
df-ral 2619(x A φx(x Aφ))
df-rex 2620(x A φx(x A φ))
df-reu 2621(∃!x A φ∃!x(x A φ))
df-rmo 2622(∃*x A φ∃*x(x A φ))
df-rab 2623{x A φ} = {x (x A φ)}
cvv 2859class V
df-v 2861V = {x x = x}
wsbc 3046wff A / xφ
df-sbc 3047([̣A / xφA {x φ})
csb 3136class [A / x]B
df-csb 3137[A / x]B = {y A / xy B}
cnin 3204class (AB)
ccompl 3205class A
cdif 3206class (A B)
cun 3207class (AB)
cin 3208class (AB)
csymdif 3209class (AB)
df-nin 3211(AB) = {x (x A x B)}
df-compl 3212A = (AA)
df-in 3213(AB) = ∼ (AB)
df-un 3214(AB) = ( ∼ A ⩃ ∼ B)
df-dif 3215(A B) = (A ∩ ∼ B)
df-symdif 3216(AB) = ((A B) ∪ (B A))
wss 3257wff A B
wpss 3258wff AB
df-ss 3259(A B ↔ (AB) = A)
df-pss 3261(AB ↔ (A B AB))
c0 3550class
df-nul 3551 = (V V)
cif 3662class if(φ, A, B)
df-if 3663 if(φ, A, B) = {x ((x A φ) (x B ¬ φ))}
cpw 3722class A
df-pw 3724A = {x x A}
csn 3737class {A}
cpr 3738class {A, B}
ctp 3739class {A, B, C}
df-sn 3741{A} = {x x = A}
df-pr 3742{A, B} = ({A} ∪ {B})
df-tp 3743{A, B, C} = ({A, B} ∪ {C})
cuni 3891class A
df-uni 3892A = {x y(x y y A)}
cint 3926class A
df-int 3927A = {x y(y Ax y)}
ciun 3969class x A B
ciin 3970class x A B
df-iun 3971x A B = {y x A y B}
df-iin 3972x A B = {y x A y B}
copk 4057class A, B
df-opk 4058A, B⟫ = {{A}, {A, B}}
ax-nin 4078zw(w z ↔ (w x w y))
ax-xp 4079yz(z ywt(z = ⟪w, t t x))
ax-cnv 4080yzw(⟪z, w y ↔ ⟪w, z x)
ax-1c 4081xy(y xzw(w yw = z))
ax-sset 4082xyz(⟪y, z xw(w yw z))
ax-si 4083yzw(⟪{z}, {w}⟫ y ↔ ⟪z, w x)
ax-ins2 4084yzwt(⟪{{z}}, ⟪w, t⟫⟫ y ↔ ⟪z, t x)
ax-ins3 4085yzwt(⟪{{z}}, ⟪w, t⟫⟫ y ↔ ⟪z, w x)
ax-typlower 4086yz(z yww, {z}⟫ x)
ax-sn 4087yz(z yz = x)
cuni1 4133class 1A
c1c 4134class 1c
cpw1 4135class 1A
df-1c 41361c = {x y x = {y}}
df-pw1 41371A = (A ∩ 1c)
df-uni1 41381A = (A ∩ 1c)
cxpk 4174class (A ×k B)
ccnvk 4175class kA
cins2k 4176class Ins2k A
cins3k 4177class Ins3k A
cp6 4178class P6 A
cimak 4179class (Ak B)
ccomk 4180class (A k B)
csik 4181class SIk A
cimagek 4182class ImagekA
cssetk 4183class Sk
cidk 4184class Ik
df-xpk 4185(A ×k B) = {x yz(x = ⟪y, z (y A z B))}
df-cnvk 4186kA = {x yz(x = ⟪y, zz, y A)}
df-ins2k 4187 Ins2k A = {x yz(x = ⟪y, z tuv(y = {{t}} z = ⟪u, vt, v A))}
df-ins3k 4188 Ins3k A = {x yz(x = ⟪y, z tuv(y = {{t}} z = ⟪u, vt, u A))}
df-imak 4189(Ak B) = {x y By, x A}
df-cok 4190(A k B) = (( Ins2k AIns3k kB) “k V)
df-p6 4191 P6 A = {x (V ×k {{x}}) A}
df-sik 4192 SIk A = {x yz(x = ⟪y, z tu(y = {t} z = {u} t, u A))}
df-ssetk 4193 Sk = {x yz(x = ⟪y, z y z)}
df-imagek 4194ImagekA = ((V ×k V) (( Ins2k SkIns3k ( Sk k k SIk A)) “k 111c))
df-idk 4195 Ik = {x yz(x = ⟪y, z y = z)}
cio 4337class (℩xφ)
df-iota 4339(℩xφ) = {y {x φ} = {y}}
cnnc 4373class Nn
c0c 4374class 0c
cplc 4375class (A +c B)
cfin 4376class Fin
df-0c 43770c = {}
df-addc 4378(A +c B) = {x y A z B ((yz) = x = (yz))}
df-nnc 4379 Nn = {b (0c b y b (y +c 1c) b)}
df-fin 4380 Fin = Nn
clefin 4432class fin
cltfin 4433class <fin
cncfin 4434class Ncfin A
ctfin 4435class Tfin A
cevenfin 4436class Evenfin
coddfin 4437class Oddfin
wsfin 4438wff Sfin (A, B)
cspfin 4439class Spfin
df-lefin 4440fin = {x yz(x = ⟪y, z w Nn z = (y +c w))}
df-ltfin 4441 <fin = {x mn(x = ⟪m, n (m p Nn n = ((m +c p) +c 1c)))}
df-ncfin 4442 Ncfin A = (℩x(x Nn A x))
df-tfin 4443 Tfin M = if(M = , , (℩n(n Nn a M 1a n)))
df-evenfin 4444 Evenfin = {x (n Nn x = (n +c n) x)}
df-oddfin 4445 Oddfin = {x (n Nn x = ((n +c n) +c 1c) x)}
df-sfin 4446( Sfin (M, N) ↔ (M Nn N Nn a(1a M a N)))
df-spfin 4447 Spfin = {a ( Ncfin V a x a z( Sfin (z, x) → z a))}
cop 4561class A, B
cphi 4562class Phi A
cproj1 4563class Proj1 A
cproj2 4564class Proj2 A
df-phi 4565 Phi A = {y x A y = if(x Nn , (x +c 1c), x)}
df-op 4566A, B = ({x y A x = Phi y} ∪ {x y B x = ( Phi y ∪ {0c})})
df-proj1 4567 Proj1 A = {x Phi x A}
df-proj2 4568 Proj2 A = {x ( Phi x ∪ {0c}) A}
copab 4622class {x, y φ}
df-opab 4623{x, y φ} = {z xy(z = x, y φ)}
wbr 4639wff ARB
df-br 4640(ARBA, B R)
c1st 4717class 1st
cswap 4718class Swap
csset 4719class S
csi 4720class SI A
ccom 4721class (A B)
cima 4722class (AB)
df-1st 47231st = {x, y z x = y, z}
df-swap 4724 Swap = {x, y zw(x = z, w y = w, z)}
df-sset 4725 S = {x, y x y}
df-co 4726(A B) = {x, y z(xBz zAy)}
df-ima 4727(AB) = {x y B yAx}
df-si 4728 SI A = {x, y zw(x = {z} y = {w} zAw)}
cep 4762class E
cid 4763class I
df-eprel 4764 E = {x, y x y}
df-id 4767 I = {x, y x = y}
cxp 4770class (A × B)
ccnv 4771class A
cdm 4772class dom A
crn 4773class ran A
cres 4774class (A B)
wfun 4775wff Fun A
wfn 4776wff A Fn B
wf 4777wff F:A–→B
wf1 4778wff F:A1-1B
wfo 4779wff F:AontoB
wf1o 4780wff F:A1-1-ontoB
cfv 4781class (FA)
wiso 4782wff H Isom R, S (A, B)
c2nd 4783class 2nd
df-xp 4784(A × B) = {x, y (x A y B)}
df-cnv 4785A = {x, y yAx}
df-rn 4786ran A = (A “ V)
df-dm 4787dom A = ran A
df-res 4788(A B) = (A ∩ (B × V))
df-fun 4789(Fun A ↔ (A A) I )
df-fn 4790(A Fn B ↔ (Fun A dom A = B))
df-f 4791(F:A–→B ↔ (F Fn A ran F B))
df-f1 4792(F:A1-1B ↔ (F:A–→B Fun F))
df-fo 4793(F:AontoB ↔ (F Fn A ran F = B))
df-f1o 4794(F:A1-1-ontoB ↔ (F:A1-1B F:AontoB))
df-fv 4795(FA) = (℩xAFx)
df-iso 4796(H Isom R, S (A, B) ↔ (H:A1-1-ontoB x A y A (xRy ↔ (Hx)S(Hy))))
df-2nd 47972nd = {x, y z x = z, y}
co 5525class (AFB)
df-ov 5526(AFB) = (FA, B)
coprab 5527class {x, y, z φ}
df-oprab 5528{x, y, z φ} = {w xyz(w = x, y, z φ)}
cmpt 5651class (x A B)
df-mpt 5652(x A B) = {x, y (x A y = B)}
cmpt2 5653class (x A, y B C)
df-mpt2 5654(x A, y B C) = {x, y, z ((x A y B) z = C)}
ctxp 5735class (AB)
df-txp 5736(AB) = ((1st A) ∩ (2nd B))
cpprod 5737class PProd (A, B)
df-pprod 5738 PProd (A, B) = ((A 1st ) ⊗ (B 2nd ))
cfix 5739class Fix A
df-fix 5740 Fix A = ran (A ∩ I )
ccup 5741class Cup
df-cup 5742 Cup = (x V, y V (xy))
cdisj 5743class Disj
df-disj 5744 Disj = {x, y (xy) = }
caddcfn 5745class AddC
df-addcfn 5746 AddC = (x V, y V (x +c y))
ccompose 5747class Compose
df-compose 5748 Compose = (x V, y V (x y))
cins2 5749class Ins2 A
df-ins2 5750 Ins2 A = (V ⊗ A)
cins3 5751class Ins3 A
df-ins3 5752 Ins3 A = (A ⊗ V)
cimage 5753class ImageA
df-image 5754ImageA = ∼ (( Ins2 S Ins3 ( S SI A)) “ 1c)
cins4 5755class Ins4 A
df-ins4 5756 Ins4 A = ((1st ⊗ ((1st 2nd ) ⊗ ((1st 2nd ) 2nd ))) “ A)
csi3 5757class SI3 A
df-si3 5758 SI3 A = (( SI 1st ⊗ ( SI (1st 2nd ) ⊗ SI (2nd 2nd ))) “ 1A)
cfuns 5759class Funs
df-funs 5760 Funs = {f Fun f}
cfns 5761class Fns
df-fns 5762 Fns = {f, a f Fn a}
ccross 5763class Cross
df-cross 5764 Cross = (x V, y V (x × y))
cpw1fn 5765class Pw1Fn
df-pw1fn 5766 Pw1Fn = (x 1c 1x)
cfullfun 5767class FullFun F
df-fullfun 5768 FullFun F = ((( I F) ( ∼ I F)) ∪ ( ∼ dom (( I F) ( ∼ I F)) × {}))
cdomfn 5769class Dom
df-domfn 5770 Dom = (x V dom x)
cranfn 5771class Ran
df-ranfn 5772 Ran = (x V ran x)
cclos1 5872class Clos1 (A, R)
df-clos1 5873 Clos1 (S, R) = {a (S a (Ra) a)}
ctrans 5888class Trans
cref 5889class Ref
cantisym 5890class Antisym
cpartial 5891class Po
cconnex 5892class Connex
cstrict 5893class Or
cfound 5894class Fr
cwe 5895class We
cext 5896class Ext
csym 5897class Sym
cer 5898class Er
df-trans 5899 Trans = {r, a x a y a z a ((xry yrz) → xrz)}
df-ref 5900 Ref = {r, a x a xrx}
df-antisym 5901 Antisym = {r, a x a y a ((xry yrx) → x = y)}
df-partial 5902 Po = (( RefTrans ) ∩ Antisym )
df-connex 5903 Connex = {r, a x a y a (xry yrx)}
df-strict 5904 Or = ( PoConnex )
df-found 5905 Fr = {r, a x((x a x) → z x y x (yrzy = z))}
df-we 5906 We = ( OrFr )
df-ext 5907 Ext = {r, a x a y a (z a (zrxzry) → x = y)}
df-sym 5908 Sym = {r, a x a y a (xryyrx)}
df-er 5909 Er = ( SymTrans )
cec 5945class [A]R
cqs 5946class (A / R)
df-ec 5947[A]R = (R “ {A})
df-qs 5951(A / R) = {y x A y = [x]R}
cmap 5999class m
cpm 6000class pm
df-map 6001m = (x V, y V {f f:y–→x})
df-pm 6002pm = (x V, y V {f (y × x) Fun f})
cen 6028class
df-en 6029 ≈ = {x, y f f:x1-1-ontoy}
cncs 6088class NC
clec 6089class c
cltc 6090class <c
cnc 6091class Nc A
cmuc 6092class ·c
ctc 6093class Tc A
c2c 6094class 2c
c3c 6095class 3c
cce 6096class c
ctcfn 6097class TcFn
df-ncs 6098 NC = (V / ≈ )
df-lec 6099c = {a, b x a y b x y}
df-ltc 6100 <c = ( ≤c I )
df-nc 6101 Nc A = [A] ≈
df-muc 6102 ·c = (m NC , n NC {a b m g n a ≈ (b × g)})
df-tc 6103 Tc A = (℩b(b NC x A b = Nc 1x))
df-2c 61042c = Nc {, V}
df-3c 61053c = Nc {, V, (V {})}
df-ce 6106c = (n NC , m NC {g ab(1a n 1b m g ≈ (am b))})
df-tcfn 6107TcFn = (x 1c Tc x)
cspac 6273class Spac
df-spac 6274 Spac = (m NC Clos1 ({m}, {x, y (x NC y NC y = (2cc x))}))
cfrec 6309class FRec (F, I)
df-frec 6310 FRec (F, I) = Clos1 ({0c, I}, PProd ((x V (x +c 1c)), F))
ccan 6323class Can
df-can 6324 Can = {x 1xx}
cscan 6325class SCan
df-scan 6326 SCan = {x (y x {y}) V}
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