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| Description: Lemma for proving that the union of two finite sets is finite. |
| Ref | Expression |
|---|---|
| unfilem1.1 |
|
| unfilem1.2 |
|
| unfilem1.3 |
|
| Ref | Expression |
|---|---|
| unfilem2 |
|
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | df-f1o 3187 |
. 2
| |
| 2 | f1fv 3859 |
. . 3
| |
| 3 | df-fo 3186 |
. . . . 5
| |
| 4 | oprex 3968 |
. . . . . 6
| |
| 5 | unfilem1.3 |
. . . . . 6
| |
| 6 | 4, 5 | fnopab2 3604 |
. . . . 5
|
| 7 | unfilem1.1 |
. . . . . 6
| |
| 8 | unfilem1.2 |
. . . . . 6
| |
| 9 | 7, 8, 5 | unfilem1 4524 |
. . . . 5
|
| 10 | 3, 6, 9 | mpbir2an 728 |
. . . 4
|
| 11 | fof 3657 |
. . . 4
| |
| 12 | 10, 11 | ax-mp 7 |
. . 3
|
| 13 | opreq2 3954 |
. . . . . . . 8
| |
| 14 | oprex 3968 |
. . . . . . . 8
| |
| 15 | 13, 5, 14 | fvopab4 3765 |
. . . . . . 7
|
| 16 | opreq2 3954 |
. . . . . . . 8
| |
| 17 | oprex 3968 |
. . . . . . . 8
| |
| 18 | 16, 5, 17 | fvopab4 3765 |
. . . . . . 7
|
| 19 | 15, 18 | eqeqan12d 1482 |
. . . . . 6
|
| 20 | nnacan 4226 |
. . . . . . . 8
| |
| 21 | 7, 20 | mp3an1 900 |
. . . . . . 7
|
| 22 | elnn 3132 |
. . . . . . . 8
| |
| 23 | 8, 22 | mpan2 694 |
. . . . . . 7
|
| 24 | elnn 3132 |
. . . . . . . 8
| |
| 25 | 8, 24 | mpan2 694 |
. . . . . . 7
|
| 26 | 21, 23, 25 | syl2an 454 |
. . . . . 6
|
| 27 | 19, 26 | bitrd 526 |
. . . . 5
|
| 28 | 27 | biimpd 153 |
. . . 4
|
| 29 | 28 | rgen2a 1691 |
. . 3
|
| 30 | 2, 12, 29 | mpbir2an 728 |
. 2
|
| 31 | 1, 30, 10 | mpbir2an 728 |
1
|
| Colors of variables: wff set class |
| Syntax hints: |
| This theorem is referenced by: unfilem3 4526 |
| This theorem was proved from axioms: ax-1 4 ax-2 5 ax-3 6 ax-mp 7 ax-7 959 ax-gen 960 ax-8 961 ax-9 962 ax-10 963 ax-11 964 ax-12 965 ax-13 966 ax-14 967 ax-17 968 ax-4 970 ax-5o 972 ax-6o 975 ax-9o 1119 ax-10o 1136 ax-16 1206 ax-11o 1213 ax-ext 1452 ax-rep 2683 ax-sep 2693 ax-nul 2700 ax-pow 2732 ax-pr 2769 ax-un 2857 |
| This theorem depends on definitions: df-bi 147 df-or 224 df-an 225 df-3or 774 df-3an 775 df-ex 978 df-sb 1168 df-eu 1375 df-mo 1376 df-clab 1457 df-cleq 1462 df-clel 1465 df-ne 1579 df-ral 1641 df-rex 1642 df-reu 1643 df-rab 1644 df-v 1803 df-sbc 1932 df-csb 1992 df-dif 2039 df-un 2040 df-in 2041 df-ss 2043 df-nul 2271 df-if 2352 df-pw 2392 df-sn 2402 df-pr 2403 df-tp 2405 df-op 2406 df-uni 2494 df-int 2524 df-iun 2558 df-br 2610 df-opab 2657 df-tr 2671 df-eprel 2821 df-id 2824 df-po 2831 df-so 2841 df-fr 2907 df-we 2924 df-ord 2941 df-on 2942 df-lim 2943 df-suc 2944 df-om 3122 df-xp 3174 df-rel 3175 df-cnv 3176 df-co 3177 df-dm 3178 df-rn 3179 df-res 3180 df-ima 3181 df-fun 3182 df-fn 3183 df-f 3184 df-f1 3185 df-fo 3186 df-f1o 3187 df-fv 3188 df-rdg 3917 df-opr 3950 df-oprab 3951 df-oadd 4119 |