![]() |
Intuitionistic Logic Explorer |
< Previous
Next >
Nearby theorems |
|
Mirrors > Home > ILE Home > Th. List > fihashf1rn | GIF version |
Description: The size of a finite set which is a one-to-one function is equal to the size of the function's range. (Contributed by Jim Kingdon, 21-Feb-2022.) |
Ref | Expression |
---|---|
fihashf1rn | ⊢ ((𝐴 ∈ Fin ∧ 𝐹:𝐴–1-1→𝐵) → (♯‘𝐹) = (♯‘ran 𝐹)) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | f1fn 5442 | . . 3 ⊢ (𝐹:𝐴–1-1→𝐵 → 𝐹 Fn 𝐴) | |
2 | simpl 109 | . . 3 ⊢ ((𝐴 ∈ Fin ∧ 𝐹:𝐴–1-1→𝐵) → 𝐴 ∈ Fin) | |
3 | fnfi 6965 | . . 3 ⊢ ((𝐹 Fn 𝐴 ∧ 𝐴 ∈ Fin) → 𝐹 ∈ Fin) | |
4 | 1, 2, 3 | syl2an2 594 | . 2 ⊢ ((𝐴 ∈ Fin ∧ 𝐹:𝐴–1-1→𝐵) → 𝐹 ∈ Fin) |
5 | f1o2ndf1 6252 | . . . 4 ⊢ (𝐹:𝐴–1-1→𝐵 → (2nd ↾ 𝐹):𝐹–1-1-onto→ran 𝐹) | |
6 | df-2nd 6165 | . . . . . . . . 9 ⊢ 2nd = (𝑥 ∈ V ↦ ∪ ran {𝑥}) | |
7 | 6 | funmpt2 5274 | . . . . . . . 8 ⊢ Fun 2nd |
8 | f1f 5440 | . . . . . . . . . . 11 ⊢ (𝐹:𝐴–1-1→𝐵 → 𝐹:𝐴⟶𝐵) | |
9 | 8 | anim2i 342 | . . . . . . . . . 10 ⊢ ((𝐴 ∈ Fin ∧ 𝐹:𝐴–1-1→𝐵) → (𝐴 ∈ Fin ∧ 𝐹:𝐴⟶𝐵)) |
10 | 9 | ancomd 267 | . . . . . . . . 9 ⊢ ((𝐴 ∈ Fin ∧ 𝐹:𝐴–1-1→𝐵) → (𝐹:𝐴⟶𝐵 ∧ 𝐴 ∈ Fin)) |
11 | fex 5765 | . . . . . . . . 9 ⊢ ((𝐹:𝐴⟶𝐵 ∧ 𝐴 ∈ Fin) → 𝐹 ∈ V) | |
12 | 10, 11 | syl 14 | . . . . . . . 8 ⊢ ((𝐴 ∈ Fin ∧ 𝐹:𝐴–1-1→𝐵) → 𝐹 ∈ V) |
13 | resfunexg 5757 | . . . . . . . 8 ⊢ ((Fun 2nd ∧ 𝐹 ∈ V) → (2nd ↾ 𝐹) ∈ V) | |
14 | 7, 12, 13 | sylancr 414 | . . . . . . 7 ⊢ ((𝐴 ∈ Fin ∧ 𝐹:𝐴–1-1→𝐵) → (2nd ↾ 𝐹) ∈ V) |
15 | f1oeq1 5468 | . . . . . . . . . 10 ⊢ ((2nd ↾ 𝐹) = 𝑓 → ((2nd ↾ 𝐹):𝐹–1-1-onto→ran 𝐹 ↔ 𝑓:𝐹–1-1-onto→ran 𝐹)) | |
16 | 15 | biimpd 144 | . . . . . . . . 9 ⊢ ((2nd ↾ 𝐹) = 𝑓 → ((2nd ↾ 𝐹):𝐹–1-1-onto→ran 𝐹 → 𝑓:𝐹–1-1-onto→ran 𝐹)) |
17 | 16 | eqcoms 2192 | . . . . . . . 8 ⊢ (𝑓 = (2nd ↾ 𝐹) → ((2nd ↾ 𝐹):𝐹–1-1-onto→ran 𝐹 → 𝑓:𝐹–1-1-onto→ran 𝐹)) |
18 | 17 | adantl 277 | . . . . . . 7 ⊢ (((𝐴 ∈ Fin ∧ 𝐹:𝐴–1-1→𝐵) ∧ 𝑓 = (2nd ↾ 𝐹)) → ((2nd ↾ 𝐹):𝐹–1-1-onto→ran 𝐹 → 𝑓:𝐹–1-1-onto→ran 𝐹)) |
19 | 14, 18 | spcimedv 2838 | . . . . . 6 ⊢ ((𝐴 ∈ Fin ∧ 𝐹:𝐴–1-1→𝐵) → ((2nd ↾ 𝐹):𝐹–1-1-onto→ran 𝐹 → ∃𝑓 𝑓:𝐹–1-1-onto→ran 𝐹)) |
20 | 19 | ex 115 | . . . . 5 ⊢ (𝐴 ∈ Fin → (𝐹:𝐴–1-1→𝐵 → ((2nd ↾ 𝐹):𝐹–1-1-onto→ran 𝐹 → ∃𝑓 𝑓:𝐹–1-1-onto→ran 𝐹))) |
21 | 20 | com13 80 | . . . 4 ⊢ ((2nd ↾ 𝐹):𝐹–1-1-onto→ran 𝐹 → (𝐹:𝐴–1-1→𝐵 → (𝐴 ∈ Fin → ∃𝑓 𝑓:𝐹–1-1-onto→ran 𝐹))) |
22 | 5, 21 | mpcom 36 | . . 3 ⊢ (𝐹:𝐴–1-1→𝐵 → (𝐴 ∈ Fin → ∃𝑓 𝑓:𝐹–1-1-onto→ran 𝐹)) |
23 | 22 | impcom 125 | . 2 ⊢ ((𝐴 ∈ Fin ∧ 𝐹:𝐴–1-1→𝐵) → ∃𝑓 𝑓:𝐹–1-1-onto→ran 𝐹) |
24 | fihasheqf1oi 10798 | . . . 4 ⊢ ((𝐹 ∈ Fin ∧ 𝑓:𝐹–1-1-onto→ran 𝐹) → (♯‘𝐹) = (♯‘ran 𝐹)) | |
25 | 24 | ex 115 | . . 3 ⊢ (𝐹 ∈ Fin → (𝑓:𝐹–1-1-onto→ran 𝐹 → (♯‘𝐹) = (♯‘ran 𝐹))) |
26 | 25 | exlimdv 1830 | . 2 ⊢ (𝐹 ∈ Fin → (∃𝑓 𝑓:𝐹–1-1-onto→ran 𝐹 → (♯‘𝐹) = (♯‘ran 𝐹))) |
27 | 4, 23, 26 | sylc 62 | 1 ⊢ ((𝐴 ∈ Fin ∧ 𝐹:𝐴–1-1→𝐵) → (♯‘𝐹) = (♯‘ran 𝐹)) |
Colors of variables: wff set class |
Syntax hints: → wi 4 ∧ wa 104 = wceq 1364 ∃wex 1503 ∈ wcel 2160 Vcvv 2752 {csn 3607 ∪ cuni 3824 ran crn 4645 ↾ cres 4646 Fun wfun 5229 Fn wfn 5230 ⟶wf 5231 –1-1→wf1 5232 –1-1-onto→wf1o 5234 ‘cfv 5235 2nd c2nd 6163 Fincfn 6765 ♯chash 10786 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-ia1 106 ax-ia2 107 ax-ia3 108 ax-in1 615 ax-in2 616 ax-io 710 ax-5 1458 ax-7 1459 ax-gen 1460 ax-ie1 1504 ax-ie2 1505 ax-8 1515 ax-10 1516 ax-11 1517 ax-i12 1518 ax-bndl 1520 ax-4 1521 ax-17 1537 ax-i9 1541 ax-ial 1545 ax-i5r 1546 ax-13 2162 ax-14 2163 ax-ext 2171 ax-coll 4133 ax-sep 4136 ax-nul 4144 ax-pow 4192 ax-pr 4227 ax-un 4451 ax-setind 4554 ax-iinf 4605 ax-cnex 7931 ax-resscn 7932 ax-1cn 7933 ax-1re 7934 ax-icn 7935 ax-addcl 7936 ax-addrcl 7937 ax-mulcl 7938 ax-addcom 7940 ax-addass 7942 ax-distr 7944 ax-i2m1 7945 ax-0lt1 7946 ax-0id 7948 ax-rnegex 7949 ax-cnre 7951 ax-pre-ltirr 7952 ax-pre-ltwlin 7953 ax-pre-lttrn 7954 ax-pre-ltadd 7956 |
This theorem depends on definitions: df-bi 117 df-dc 836 df-3or 981 df-3an 982 df-tru 1367 df-fal 1370 df-nf 1472 df-sb 1774 df-eu 2041 df-mo 2042 df-clab 2176 df-cleq 2182 df-clel 2185 df-nfc 2321 df-ne 2361 df-nel 2456 df-ral 2473 df-rex 2474 df-reu 2475 df-rab 2477 df-v 2754 df-sbc 2978 df-csb 3073 df-dif 3146 df-un 3148 df-in 3150 df-ss 3157 df-nul 3438 df-if 3550 df-pw 3592 df-sn 3613 df-pr 3614 df-op 3616 df-uni 3825 df-int 3860 df-iun 3903 df-br 4019 df-opab 4080 df-mpt 4081 df-tr 4117 df-id 4311 df-iord 4384 df-on 4386 df-ilim 4387 df-suc 4389 df-iom 4608 df-xp 4650 df-rel 4651 df-cnv 4652 df-co 4653 df-dm 4654 df-rn 4655 df-res 4656 df-ima 4657 df-iota 5196 df-fun 5237 df-fn 5238 df-f 5239 df-f1 5240 df-fo 5241 df-f1o 5242 df-fv 5243 df-riota 5851 df-ov 5898 df-oprab 5899 df-mpo 5900 df-2nd 6165 df-recs 6329 df-frec 6415 df-1o 6440 df-er 6558 df-en 6766 df-dom 6767 df-fin 6768 df-pnf 8023 df-mnf 8024 df-xr 8025 df-ltxr 8026 df-le 8027 df-sub 8159 df-neg 8160 df-inn 8949 df-n0 9206 df-z 9283 df-uz 9558 df-ihash 10787 |
This theorem is referenced by: (None) |
Copyright terms: Public domain | W3C validator |