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| Description: The union of the image of a mapping to cardinals is a cardinal. Proposition 11.16 of [TakeutiZaring] p. 104. |
| Ref | Expression |
|---|---|
| carduniima |
|
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | funimaexg 3567 |
. . . . 5
| |
| 2 | ffun 3621 |
. . . . 5
| |
| 3 | 1, 2 | sylan 448 |
. . . 4
|
| 4 | 3 | expcom 374 |
. . 3
|
| 5 | carduni 4838 |
. . . 4
| |
| 6 | ffn 3619 |
. . . . . . . . 9
| |
| 7 | fnima 3596 |
. . . . . . . . 9
| |
| 8 | 6, 7 | syl 10 |
. . . . . . . 8
|
| 9 | frn 3624 |
. . . . . . . 8
| |
| 10 | 8, 9 | eqsstrd 2091 |
. . . . . . 7
|
| 11 | 10 | sseld 2063 |
. . . . . 6
|
| 12 | iscard3 4868 |
. . . . . 6
| |
| 13 | 11, 12 | syl6ibr 213 |
. . . . 5
|
| 14 | 13 | r19.21aiv 1710 |
. . . 4
|
| 15 | 5, 14 | syl5 21 |
. . 3
|
| 16 | 4, 15 | syli 54 |
. 2
|
| 17 | iscard3 4868 |
. 2
| |
| 18 | 16, 17 | syl6ib 212 |
1
|
| Colors of variables: wff set class |
| Syntax hints: |
| This theorem is referenced by: cardinfima 4871 |
| This theorem was proved from axioms: ax-1 4 ax-2 5 ax-3 6 ax-mp 7 ax-7 960 ax-gen 961 ax-8 962 ax-9 963 ax-10 964 ax-11 965 ax-12 966 ax-13 967 ax-14 968 ax-17 969 ax-4 971 ax-5o 973 ax-6o 976 ax-9o 1121 ax-10o 1138 ax-16 1208 ax-11o 1216 ax-ext 1457 ax-rep 2688 ax-sep 2698 ax-nul 2705 ax-pow 2737 ax-pr 2774 ax-un 2861 ax-reg 4573 ax-inf2 4605 ax-ac 4724 |
| This theorem depends on definitions: df-bi 147 df-or 224 df-an 225 df-3or 775 df-3an 776 df-ex 979 df-sb 1170 df-eu 1380 df-mo 1381 df-clab 1462 df-cleq 1467 df-clel 1470 df-ne 1584 df-ral 1646 df-rex 1647 df-reu 1648 df-rab 1649 df-v 1808 df-sbc 1938 df-dif 2045 df-un 2046 df-in 2047 df-ss 2049 df-pss 2051 df-nul 2277 df-if 2358 df-pw 2398 df-sn 2408 df-pr 2409 df-tp 2411 df-op 2412 df-uni 2499 df-int 2529 df-iun 2563 df-br 2615 df-opab 2662 df-tr 2676 df-eprel 2827 df-id 2830 df-po 2835 df-so 2845 df-fr 2912 df-we 2929 df-ord 2946 df-on 2947 df-lim 2948 df-suc 2949 df-om 3127 df-xp 3179 df-rel 3180 df-cnv 3181 df-co 3182 df-dm 3183 df-rn 3184 df-res 3185 df-ima 3186 df-fun 3187 df-fn 3188 df-f 3189 df-f1 3190 df-fo 3191 df-f1o 3192 df-fv 3193 df-rdg 3923 df-er 4251 df-en 4357 df-dom 4358 df-sdom 4359 df-card 4796 df-aleph 4797 |