Theorem 0map0sn0 8833

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 6723	. . 3 ⊢ (𝑓:∅⟶∅ ↔ 𝑓 = ∅)
2	1	abbii 2803	. 2 ⊢ {𝑓 ∣ 𝑓:∅⟶∅} = {𝑓 ∣ 𝑓 = ∅}
3		0ex 5242	. . 3 ⊢ ∅ ∈ V
4	3, 3	mapval 8785	. 2 ⊢ (∅ ↑m ∅) = {𝑓 ∣ 𝑓:∅⟶∅}
5		df-sn 4568	. 2 ⊢ {∅} = {𝑓 ∣ 𝑓 = ∅}
6	2, 4, 5	3eqtr4i 2769	1 ⊢ (∅ ↑m ∅) = {∅}

Syntax hints:   = wceq 1542  {cab 2714  ∅c0 4273  {csn 4567  ⟶wf 6494  (class class class)co 7367   ↑_m cmap 8773

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1797  ax-4 1811  ax-5 1912  ax-6 1969  ax-7 2010  ax-8 2116  ax-9 2124  ax-10 2147  ax-11 2163  ax-12 2185  ax-ext 2708  ax-sep 5231  ax-nul 5241  ax-pow 5307  ax-pr 5375  ax-un 7689

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 849  df-3an 1089  df-tru 1545  df-fal 1555  df-ex 1782  df-nf 1786  df-sb 2069  df-mo 2539  df-eu 2569  df-clab 2715  df-cleq 2728  df-clel 2811  df-nfc 2885  df-ral 3052  df-rex 3062  df-rab 3390  df-v 3431  df-sbc 3729  df-dif 3892  df-un 3894  df-in 3896  df-ss 3906  df-nul 4274  df-if 4467  df-pw 4543  df-sn 4568  df-pr 4570  df-op 4574  df-uni 4851  df-br 5086  df-opab 5148  df-id 5526  df-xp 5637  df-rel 5638  df-cnv 5639  df-co 5640  df-dm 5641  df-rn 5642  df-iota 6454  df-fun 6500  df-fn 6501  df-f 6502  df-fv 6506  df-ov 7370  df-oprab 7371  df-mpo 7372  df-map 8775

This theorem is referenced by:  efmndbas0  18859  symgvalstruct  19372  setc1ohomfval  49968  setc1ocofval  49969