Proof of Theorem mapsn
| Step | Hyp | Ref
| Expression |
| 1 | | map0.1 |
. . . 4
⊢ A
∈ V |
| 2 | | snex 1859 |
. . . 4
⊢ {B}
∈ V |
| 3 | 1, 2 | elmap 3265 |
. . 3
⊢ (f
∈ (A ↑m
{B}) ↔ f:{B}–→A) |
| 4 | | map0.2 |
. . . . . . . . 9
⊢ B
∈ V |
| 5 | 4 | snid 1830 |
. . . . . . . 8
⊢ B
∈ {B} |
| 6 | | fneu2 2729 |
. . . . . . . . 9
⊢ ((f Fn
{B} ∧ B ∈ {B})
→ ∃!y〈B, y〉
∈ f) |
| 7 | | ffn 2752 |
. . . . . . . . 9
⊢ (f:{B}–→A
→ f Fn {B}) |
| 8 | 6, 7 | sylan 343 |
. . . . . . . 8
⊢ ((f:{B}–→A
∧ B ∈ {B}) → ∃!y〈B,
y〉 ∈ f) |
| 9 | 5, 8 | mpan2 519 |
. . . . . . 7
⊢ (f:{B}–→A
→ ∃!y〈B, y〉
∈ f) |
| 10 | | frel 2755 |
. . . . . . . . . . . 12
⊢ (f:{B}–→A
→ Rel f) |
| 11 | | imasn 2616 |
. . . . . . . . . . . 12
⊢ (Rel f
→ (f “ {B}) = {y∣〈B,
y〉 ∈ f}) |
| 12 | 10, 11 | syl 12 |
. . . . . . . . . . 11
⊢ (f:{B}–→A
→ (f “ {B}) = {y∣〈B,
y〉 ∈ f}) |
| 13 | | fdm 2756 |
. . . . . . . . . . . . 13
⊢ (f:{B}–→A
→ dom f = {B}) |
| 14 | | imaeq2 2603 |
. . . . . . . . . . . . 13
⊢ (dom f
= {B} → (f “ dom f)
= (f “ {B})) |
| 15 | 13, 14 | syl 12 |
. . . . . . . . . . . 12
⊢ (f:{B}–→A
→ (f “ dom f) = (f “
{B})) |
| 16 | | imadmrn 2610 |
. . . . . . . . . . . 12
⊢ (f
“ dom f) = ran f |
| 17 | 15, 16 | syl5reqr 1139 |
. . . . . . . . . . 11
⊢ (f:{B}–→A
→ (f “ {B}) = ran f) |
| 18 | 12, 17 | eqtr3d 1130 |
. . . . . . . . . 10
⊢ (f:{B}–→A
→ {y∣〈B, y〉
∈ f} = ran f) |
| 19 | 18 | cleq1d 1109 |
. . . . . . . . 9
⊢ (f:{B}–→A
→ ({y∣〈B, y〉
∈ f} = {y} ↔ ran f
= {y})) |
| 20 | 19 | biexdv 936 |
. . . . . . . 8
⊢ (f:{B}–→A
→ (∃y{y∣〈B,
y〉 ∈ f} = {y} ↔
∃yran f = {y})) |
| 21 | | eusn 1913 |
. . . . . . . 8
⊢ (∃!y〈B,
y〉 ∈ f ↔ ∃y{y∣〈B,
y〉 ∈ f} = {y}) |
| 22 | 20, 21 | syl5bb 410 |
. . . . . . 7
⊢ (f:{B}–→A
→ (∃!y〈B, y〉
∈ f ↔ ∃yran f =
{y})) |
| 23 | 9, 22 | mpbid 170 |
. . . . . 6
⊢ (f:{B}–→A
→ ∃yran f = {y}) |
| 24 | | frn 2757 |
. . . . . . . . . 10
⊢ (f:{B}–→A
→ ran f ⊆ A) |
| 25 | 24 | sseld 1506 |
. . . . . . . . 9
⊢ (f:{B}–→A
→ (y ∈ ran f → y
∈ A)) |
| 26 | | visset 1350 |
. . . . . . . . . . 11
⊢ y
∈ V |
| 27 | 26 | snid 1830 |
. . . . . . . . . 10
⊢ y
∈ {y} |
| 28 | | eleq2 1150 |
. . . . . . . . . 10
⊢ (ran f
= {y} → (y ∈ ran f
↔ y ∈ {y})) |
| 29 | 27, 28 | mpbiri 169 |
. . . . . . . . 9
⊢ (ran f
= {y} → y ∈ ran f) |
| 30 | 25, 29 | syl5 22 |
. . . . . . . 8
⊢ (f:{B}–→A
→ (ran f = {y} → y
∈ A)) |
| 31 | | feq3 2750 |
. . . . . . . . . . 11
⊢ (ran f
= {y} → (f:{B}–→ran f ↔ f:{B}–→{y})) |
| 32 | | fnforn 2791 |
. . . . . . . . . . . . 13
⊢ (f Fn
{B} ↔ f:{B}–onto→ran f) |
| 33 | 7, 32 | sylib 173 |
. . . . . . . . . . . 12
⊢ (f:{B}–→A
→ f:{B}–onto→ran f) |
| 34 | | fof 2788 |
. . . . . . . . . . . 12
⊢ (f:{B}–onto→ran f
→ f:{B}–→ran f) |
| 35 | 33, 34 | syl 12 |
. . . . . . . . . . 11
⊢ (f:{B}–→A
→ f:{B}–→ran f) |
| 36 | 31, 35 | syl5bi 183 |
. . . . . . . . . 10
⊢ (ran f
= {y} → (f:{B}–→A
→ f:{B}–→{y})) |
| 37 | 36 | com12 13 |
. . . . . . . . 9
⊢ (f:{B}–→A
→ (ran f = {y} → f:{B}–→{y})) |
| 38 | 4, 26 | fsn 2895 |
. . . . . . . . 9
⊢ (f:{B}–→{y} ↔ f =
{〈B, y〉}) |
| 39 | 37, 38 | syl6ib 185 |
. . . . . . . 8
⊢ (f:{B}–→A
→ (ran f = {y} → f =
{〈B, y〉})) |
| 40 | 30, 39 | jcad 455 |
. . . . . . 7
⊢ (f:{B}–→A
→ (ran f = {y} → (y
∈ A ∧ f = {〈B,
y〉}))) |
| 41 | 40 | 19.22dv 947 |
. . . . . 6
⊢ (f:{B}–→A
→ (∃yran f = {y} →
∃y(y ∈ A ∧
f = {〈B, y〉}))) |
| 42 | 23, 41 | mpd 46 |
. . . . 5
⊢ (f:{B}–→A
→ ∃y(y ∈ A ∧
f = {〈B, y〉})) |
| 43 | | df-rex 1206 |
. . . . 5
⊢ (∃y ∈ A
f = {〈B, y〉}
↔ ∃y(y ∈ A ∧
f = {〈B, y〉})) |
| 44 | 42, 43 | sylibr 175 |
. . . 4
⊢ (f:{B}–→A
→ ∃y ∈ A f =
{〈B, y〉}) |
| 45 | | fss 2759 |
. . . . . . . 8
⊢ ((f:{B}–→{y} ∧ {y}
⊆ A) → f:{B}–→A) |
| 46 | 4, 26 | f1osn 2827 |
. . . . . . . . . 10
⊢ {〈B, y〉}:{B}–1-1-onto→{y} |
| 47 | | f1oeq1 2795 |
. . . . . . . . . 10
⊢ (f =
{〈B, y〉} → (f:{B}–1-1-onto→{y} ↔
{〈B, y〉}:{B}–1-1-onto→{y})) |
| 48 | 46, 47 | mpbiri 169 |
. . . . . . . . 9
⊢ (f =
{〈B, y〉} → f:{B}–1-1-onto→{y}) |
| 49 | | f1of 2800 |
. . . . . . . . 9
⊢ (f:{B}–1-1-onto→{y} →
f:{B}–→{y}) |
| 50 | 48, 49 | syl 12 |
. . . . . . . 8
⊢ (f =
{〈B, y〉} → f:{B}–→{y}) |
| 51 | | snssi 1851 |
. . . . . . . 8
⊢ (y
∈ A → {y} ⊆ A) |
| 52 | 45, 50, 51 | syl2an 349 |
. . . . . . 7
⊢ ((f =
{〈B, y〉} ∧ y
∈ A) → f:{B}–→A) |
| 53 | 52 | exp 291 |
. . . . . 6
⊢ (f =
{〈B, y〉} → (y ∈ A
→ f:{B}–→A)) |
| 54 | 53 | com12 13 |
. . . . 5
⊢ (y
∈ A → (f = {〈B,
y〉} → f:{B}–→A)) |
| 55 | 54 | r19.23aiv 1284 |
. . . 4
⊢ (∃y ∈ A
f = {〈B, y〉}
→ f:{B}–→A) |
| 56 | 44, 55 | impbi 139 |
. . 3
⊢ (f:{B}–→A
↔ ∃y ∈ A f =
{〈B, y〉}) |
| 57 | 3, 56 | bitr 151 |
. 2
⊢ (f
∈ (A ↑m
{B}) ↔ ∃y ∈ A
f = {〈B, y〉}) |
| 58 | 57 | biabri 1180 |
1
⊢ (A
↑m {B}) = {f∣∃y
∈ A f = {〈B,
y〉}} |