Metamath Proof Explorer


Theorem preimageiingt

Description: A preimage of a left-closed, unbounded above interval, expressed as an indexed intersection of preimages of open, unbounded above intervals. (Contributed by Glauco Siliprandi, 26-Jun-2021)

Ref Expression
Hypotheses preimageiingt.x x φ
preimageiingt.b φ x A B *
preimageiingt.c φ C
Assertion preimageiingt φ x A | C B = n x A | C 1 n < B

Proof

Step Hyp Ref Expression
1 preimageiingt.x x φ
2 preimageiingt.b φ x A B *
3 preimageiingt.c φ C
4 simpllr φ x A C B n x A
5 3 adantr φ n C
6 nnrecre n 1 n
7 6 adantl φ n 1 n
8 5 7 resubcld φ n C 1 n
9 8 rexrd φ n C 1 n *
10 9 ad4ant14 φ x A C B n C 1 n *
11 3 rexrd φ C *
12 11 ad3antrrr φ x A C B n C *
13 2 ad2antrr φ x A C B n B *
14 nnrp n n +
15 rpreccl n + 1 n +
16 14 15 syl n 1 n +
17 16 adantl φ n 1 n +
18 5 17 ltsubrpd φ n C 1 n < C
19 18 ad4ant14 φ x A C B n C 1 n < C
20 simplr φ x A C B n C B
21 10 12 13 19 20 xrltletrd φ x A C B n C 1 n < B
22 4 21 jca φ x A C B n x A C 1 n < B
23 rabid x x A | C 1 n < B x A C 1 n < B
24 22 23 sylibr φ x A C B n x x A | C 1 n < B
25 24 ralrimiva φ x A C B n x x A | C 1 n < B
26 vex x V
27 eliin x V x n x A | C 1 n < B n x x A | C 1 n < B
28 26 27 ax-mp x n x A | C 1 n < B n x x A | C 1 n < B
29 25 28 sylibr φ x A C B x n x A | C 1 n < B
30 29 ex φ x A C B x n x A | C 1 n < B
31 30 ex φ x A C B x n x A | C 1 n < B
32 1 31 ralrimi φ x A C B x n x A | C 1 n < B
33 nfcv _ x
34 nfrab1 _ x x A | C 1 n < B
35 33 34 nfiin _ x n x A | C 1 n < B
36 35 rabssf x A | C B n x A | C 1 n < B x A C B x n x A | C 1 n < B
37 32 36 sylibr φ x A | C B n x A | C 1 n < B
38 nnn0
39 iinrab n x A | C 1 n < B = x A | n C 1 n < B
40 38 39 ax-mp n x A | C 1 n < B = x A | n C 1 n < B
41 40 a1i φ n x A | C 1 n < B = x A | n C 1 n < B
42 9 ad4ant13 φ x A n C 1 n < B C 1 n *
43 2 ad2antrr φ x A n C 1 n < B B *
44 simpr φ x A n C 1 n < B C 1 n < B
45 42 43 44 xrltled φ x A n C 1 n < B C 1 n B
46 45 ex φ x A n C 1 n < B C 1 n B
47 46 ralimdva φ x A n C 1 n < B n C 1 n B
48 47 imp φ x A n C 1 n < B n C 1 n B
49 nfv n φ x A
50 nfra1 n n C 1 n < B
51 49 50 nfan n φ x A n C 1 n < B
52 3 ad2antrr φ x A n C 1 n < B C
53 2 adantr φ x A n C 1 n < B B *
54 51 52 53 xrralrecnnge φ x A n C 1 n < B C B n C 1 n B
55 48 54 mpbird φ x A n C 1 n < B C B
56 55 ex φ x A n C 1 n < B C B
57 56 ex φ x A n C 1 n < B C B
58 1 57 ralrimi φ x A n C 1 n < B C B
59 ss2rab x A | n C 1 n < B x A | C B x A n C 1 n < B C B
60 58 59 sylibr φ x A | n C 1 n < B x A | C B
61 41 60 eqsstrd φ n x A | C 1 n < B x A | C B
62 37 61 eqssd φ x A | C B = n x A | C 1 n < B