Theorem 0map0sn0 8647

Description: The set of mappings of the empty set to the empty set is the singleton containing the empty set. (Contributed by AV, 31-Mar-2024.)

Assertion

Ref	Expression
0map0sn0	⊢ (∅ ↑m ∅) = {∅}

Proof of Theorem 0map0sn0

Step	Hyp	Ref	Expression
1		f0bi 6653	. . 3 ⊢ (𝑓:∅⟶∅ ↔ 𝑓 = ∅)
2	1	abbii 2809	. 2 ⊢ {𝑓 ∣ 𝑓:∅⟶∅} = {𝑓 ∣ 𝑓 = ∅}
3		0ex 5234	. . 3 ⊢ ∅ ∈ V
4	3, 3	mapval 8601	. 2 ⊢ (∅ ↑m ∅) = {𝑓 ∣ 𝑓:∅⟶∅}
5		df-sn 4567	. 2 ⊢ {∅} = {𝑓 ∣ 𝑓 = ∅}
6	2, 4, 5	3eqtr4i 2777	1 ⊢ (∅ ↑m ∅) = {∅}

Syntax hints:   = wceq 1541  {cab 2716  ∅c0 4261  {csn 4566  ⟶wf 6426  (class class class)co 7268   ↑_m cmap 8589

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1801  ax-4 1815  ax-5 1916  ax-6 1974  ax-7 2014  ax-8 2111  ax-9 2119  ax-10 2140  ax-11 2157  ax-12 2174  ax-ext 2710  ax-sep 5226  ax-nul 5233  ax-pow 5291  ax-pr 5355  ax-un 7579

This theorem depends on definitions:  df-bi 206  df-an 396  df-or 844  df-3an 1087  df-tru 1544  df-fal 1554  df-ex 1786  df-nf 1790  df-sb 2071  df-mo 2541  df-eu 2570  df-clab 2717  df-cleq 2731  df-clel 2817  df-nfc 2890  df-ral 3070  df-rex 3071  df-rab 3074  df-v 3432  df-sbc 3720  df-dif 3894  df-un 3896  df-in 3898  df-ss 3908  df-nul 4262  df-if 4465  df-pw 4540  df-sn 4567  df-pr 4569  df-op 4573  df-uni 4845  df-br 5079  df-opab 5141  df-id 5488  df-xp 5594  df-rel 5595  df-cnv 5596  df-co 5597  df-dm 5598  df-rn 5599  df-iota 6388  df-fun 6432  df-fn 6433  df-f 6434  df-fv 6438  df-ov 7271  df-oprab 7272  df-mpo 7273  df-map 8591

This theorem is referenced by:  efmndbas0  18511  symgvalstruct  18985  symgvalstructOLD  18986