Step |
Hyp |
Ref |
Expression |
1 |
|
df-0s |
Could not format 0s = ( (/) |s (/) ) : No typesetting found for |- 0s = ( (/) |s (/) ) with typecode |- |
2 |
|
snelpwi |
|
3 |
|
nulsslt |
|
4 |
2 3
|
syl |
|
5 |
4
|
adantr |
|
6 |
|
nulssgt |
|
7 |
2 6
|
syl |
|
8 |
7
|
adantr |
|
9 |
|
id |
|
10 |
|
0ss |
|
11 |
9 10
|
eqsstrdi |
|
12 |
11
|
a1d |
|
13 |
12
|
adantl |
|
14 |
13
|
ralrimivw |
|
15 |
|
0elpw |
|
16 |
|
nulssgt |
|
17 |
15 16
|
ax-mp |
|
18 |
|
eqscut2 |
|
19 |
17 18
|
mpan |
|
20 |
19
|
adantr |
|
21 |
5 8 14 20
|
mpbir3and |
|
22 |
1 21
|
eqtr2id |
Could not format ( ( X e. No /\ ( bday ` X ) = (/) ) -> X = 0s ) : No typesetting found for |- ( ( X e. No /\ ( bday ` X ) = (/) ) -> X = 0s ) with typecode |- |
23 |
22
|
ex |
Could not format ( X e. No -> ( ( bday ` X ) = (/) -> X = 0s ) ) : No typesetting found for |- ( X e. No -> ( ( bday ` X ) = (/) -> X = 0s ) ) with typecode |- |
24 |
|
fveq2 |
Could not format ( X = 0s -> ( bday ` X ) = ( bday ` 0s ) ) : No typesetting found for |- ( X = 0s -> ( bday ` X ) = ( bday ` 0s ) ) with typecode |- |
25 |
|
bday0s |
Could not format ( bday ` 0s ) = (/) : No typesetting found for |- ( bday ` 0s ) = (/) with typecode |- |
26 |
24 25
|
eqtrdi |
Could not format ( X = 0s -> ( bday ` X ) = (/) ) : No typesetting found for |- ( X = 0s -> ( bday ` X ) = (/) ) with typecode |- |
27 |
23 26
|
impbid1 |
Could not format ( X e. No -> ( ( bday ` X ) = (/) <-> X = 0s ) ) : No typesetting found for |- ( X e. No -> ( ( bday ` X ) = (/) <-> X = 0s ) ) with typecode |- |