Step |
Hyp |
Ref |
Expression |
1 |
|
zrinitorngc.u |
|- ( ph -> U e. V ) |
2 |
|
zrinitorngc.c |
|- C = ( RngCat ` U ) |
3 |
|
zrinitorngc.z |
|- ( ph -> Z e. ( Ring \ NzRing ) ) |
4 |
|
zrinitorngc.e |
|- ( ph -> Z e. U ) |
5 |
1 2 3 4
|
zrinitorngc |
|- ( ph -> Z e. ( InitO ` C ) ) |
6 |
1 2 3 4
|
zrtermorngc |
|- ( ph -> Z e. ( TermO ` C ) ) |
7 |
|
eqid |
|- ( Base ` C ) = ( Base ` C ) |
8 |
|
eqid |
|- ( Hom ` C ) = ( Hom ` C ) |
9 |
2
|
rngccat |
|- ( U e. V -> C e. Cat ) |
10 |
1 9
|
syl |
|- ( ph -> C e. Cat ) |
11 |
3
|
eldifad |
|- ( ph -> Z e. Ring ) |
12 |
|
ringrng |
|- ( Z e. Ring -> Z e. Rng ) |
13 |
11 12
|
syl |
|- ( ph -> Z e. Rng ) |
14 |
4 13
|
elind |
|- ( ph -> Z e. ( U i^i Rng ) ) |
15 |
2 7 1
|
rngcbas |
|- ( ph -> ( Base ` C ) = ( U i^i Rng ) ) |
16 |
14 15
|
eleqtrrd |
|- ( ph -> Z e. ( Base ` C ) ) |
17 |
7 8 10 16
|
iszeroo |
|- ( ph -> ( Z e. ( ZeroO ` C ) <-> ( Z e. ( InitO ` C ) /\ Z e. ( TermO ` C ) ) ) ) |
18 |
5 6 17
|
mpbir2and |
|- ( ph -> Z e. ( ZeroO ` C ) ) |