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Theorem cncnp 21084
Description: A continuous function is continuous at all points. Theorem 7.2(g) of [Munkres] p. 107. (Contributed by NM, 15-May-2007.) (Proof shortened by Mario Carneiro, 21-Aug-2015.)
Assertion
Ref Expression
cncnp ((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) → (𝐹 ∈ (𝐽 Cn 𝐾) ↔ (𝐹:𝑋𝑌 ∧ ∀𝑥𝑋 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥))))
Distinct variable groups:   𝑥,𝐹   𝑥,𝐽   𝑥,𝐾   𝑥,𝑋   𝑥,𝑌

Proof of Theorem cncnp
Dummy variables 𝑢 𝑦 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 iscn 21039 . . . 4 ((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) → (𝐹 ∈ (𝐽 Cn 𝐾) ↔ (𝐹:𝑋𝑌 ∧ ∀𝑦𝐾 (𝐹𝑦) ∈ 𝐽)))
21simprbda 653 . . 3 (((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) → 𝐹:𝑋𝑌)
3 eqid 2622 . . . . . . 7 𝐽 = 𝐽
43cncnpi 21082 . . . . . 6 ((𝐹 ∈ (𝐽 Cn 𝐾) ∧ 𝑥 𝐽) → 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥))
54ralrimiva 2966 . . . . 5 (𝐹 ∈ (𝐽 Cn 𝐾) → ∀𝑥 𝐽𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥))
65adantl 482 . . . 4 (((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) → ∀𝑥 𝐽𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥))
7 toponuni 20719 . . . . . 6 (𝐽 ∈ (TopOn‘𝑋) → 𝑋 = 𝐽)
87ad2antrr 762 . . . . 5 (((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) → 𝑋 = 𝐽)
98raleqdv 3144 . . . 4 (((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) → (∀𝑥𝑋 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥) ↔ ∀𝑥 𝐽𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥)))
106, 9mpbird 247 . . 3 (((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) → ∀𝑥𝑋 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥))
112, 10jca 554 . 2 (((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) → (𝐹:𝑋𝑌 ∧ ∀𝑥𝑋 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥)))
12 simprl 794 . . 3 (((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ (𝐹:𝑋𝑌 ∧ ∀𝑥𝑋 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥))) → 𝐹:𝑋𝑌)
13 cnvimass 5485 . . . . . . . . . 10 (𝐹𝑦) ⊆ dom 𝐹
14 fdm 6051 . . . . . . . . . . 11 (𝐹:𝑋𝑌 → dom 𝐹 = 𝑋)
1514adantl 482 . . . . . . . . . 10 ((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ 𝑦𝐾) ∧ 𝐹:𝑋𝑌) → dom 𝐹 = 𝑋)
1613, 15syl5sseq 3653 . . . . . . . . 9 ((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ 𝑦𝐾) ∧ 𝐹:𝑋𝑌) → (𝐹𝑦) ⊆ 𝑋)
17 ssralv 3666 . . . . . . . . 9 ((𝐹𝑦) ⊆ 𝑋 → (∀𝑥𝑋 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥) → ∀𝑥 ∈ (𝐹𝑦)𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥)))
1816, 17syl 17 . . . . . . . 8 ((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ 𝑦𝐾) ∧ 𝐹:𝑋𝑌) → (∀𝑥𝑋 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥) → ∀𝑥 ∈ (𝐹𝑦)𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥)))
19 simprr 796 . . . . . . . . . . . 12 (((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ 𝑦𝐾) ∧ 𝐹:𝑋𝑌) ∧ (𝑥 ∈ (𝐹𝑦) ∧ 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥))) → 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥))
20 simpllr 799 . . . . . . . . . . . 12 (((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ 𝑦𝐾) ∧ 𝐹:𝑋𝑌) ∧ (𝑥 ∈ (𝐹𝑦) ∧ 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥))) → 𝑦𝐾)
21 ffn 6045 . . . . . . . . . . . . . 14 (𝐹:𝑋𝑌𝐹 Fn 𝑋)
2221ad2antlr 763 . . . . . . . . . . . . 13 (((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ 𝑦𝐾) ∧ 𝐹:𝑋𝑌) ∧ (𝑥 ∈ (𝐹𝑦) ∧ 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥))) → 𝐹 Fn 𝑋)
23 simprl 794 . . . . . . . . . . . . 13 (((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ 𝑦𝐾) ∧ 𝐹:𝑋𝑌) ∧ (𝑥 ∈ (𝐹𝑦) ∧ 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥))) → 𝑥 ∈ (𝐹𝑦))
24 elpreima 6337 . . . . . . . . . . . . . 14 (𝐹 Fn 𝑋 → (𝑥 ∈ (𝐹𝑦) ↔ (𝑥𝑋 ∧ (𝐹𝑥) ∈ 𝑦)))
2524simplbda 654 . . . . . . . . . . . . 13 ((𝐹 Fn 𝑋𝑥 ∈ (𝐹𝑦)) → (𝐹𝑥) ∈ 𝑦)
2622, 23, 25syl2anc 693 . . . . . . . . . . . 12 (((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ 𝑦𝐾) ∧ 𝐹:𝑋𝑌) ∧ (𝑥 ∈ (𝐹𝑦) ∧ 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥))) → (𝐹𝑥) ∈ 𝑦)
27 cnpimaex 21060 . . . . . . . . . . . 12 ((𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥) ∧ 𝑦𝐾 ∧ (𝐹𝑥) ∈ 𝑦) → ∃𝑢𝐽 (𝑥𝑢 ∧ (𝐹𝑢) ⊆ 𝑦))
2819, 20, 26, 27syl3anc 1326 . . . . . . . . . . 11 (((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ 𝑦𝐾) ∧ 𝐹:𝑋𝑌) ∧ (𝑥 ∈ (𝐹𝑦) ∧ 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥))) → ∃𝑢𝐽 (𝑥𝑢 ∧ (𝐹𝑢) ⊆ 𝑦))
29 simpllr 799 . . . . . . . . . . . . . . 15 ((((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ 𝑦𝐾) ∧ 𝐹:𝑋𝑌) ∧ (𝑥 ∈ (𝐹𝑦) ∧ 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥))) ∧ 𝑢𝐽) → 𝐹:𝑋𝑌)
30 ffun 6048 . . . . . . . . . . . . . . 15 (𝐹:𝑋𝑌 → Fun 𝐹)
3129, 30syl 17 . . . . . . . . . . . . . 14 ((((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ 𝑦𝐾) ∧ 𝐹:𝑋𝑌) ∧ (𝑥 ∈ (𝐹𝑦) ∧ 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥))) ∧ 𝑢𝐽) → Fun 𝐹)
32 simp-4l 806 . . . . . . . . . . . . . . . 16 (((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ 𝑦𝐾) ∧ 𝐹:𝑋𝑌) ∧ (𝑥 ∈ (𝐹𝑦) ∧ 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥))) → 𝐽 ∈ (TopOn‘𝑋))
33 toponss 20731 . . . . . . . . . . . . . . . 16 ((𝐽 ∈ (TopOn‘𝑋) ∧ 𝑢𝐽) → 𝑢𝑋)
3432, 33sylan 488 . . . . . . . . . . . . . . 15 ((((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ 𝑦𝐾) ∧ 𝐹:𝑋𝑌) ∧ (𝑥 ∈ (𝐹𝑦) ∧ 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥))) ∧ 𝑢𝐽) → 𝑢𝑋)
3529, 14syl 17 . . . . . . . . . . . . . . 15 ((((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ 𝑦𝐾) ∧ 𝐹:𝑋𝑌) ∧ (𝑥 ∈ (𝐹𝑦) ∧ 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥))) ∧ 𝑢𝐽) → dom 𝐹 = 𝑋)
3634, 35sseqtr4d 3642 . . . . . . . . . . . . . 14 ((((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ 𝑦𝐾) ∧ 𝐹:𝑋𝑌) ∧ (𝑥 ∈ (𝐹𝑦) ∧ 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥))) ∧ 𝑢𝐽) → 𝑢 ⊆ dom 𝐹)
37 funimass3 6333 . . . . . . . . . . . . . 14 ((Fun 𝐹𝑢 ⊆ dom 𝐹) → ((𝐹𝑢) ⊆ 𝑦𝑢 ⊆ (𝐹𝑦)))
3831, 36, 37syl2anc 693 . . . . . . . . . . . . 13 ((((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ 𝑦𝐾) ∧ 𝐹:𝑋𝑌) ∧ (𝑥 ∈ (𝐹𝑦) ∧ 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥))) ∧ 𝑢𝐽) → ((𝐹𝑢) ⊆ 𝑦𝑢 ⊆ (𝐹𝑦)))
3938anbi2d 740 . . . . . . . . . . . 12 ((((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ 𝑦𝐾) ∧ 𝐹:𝑋𝑌) ∧ (𝑥 ∈ (𝐹𝑦) ∧ 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥))) ∧ 𝑢𝐽) → ((𝑥𝑢 ∧ (𝐹𝑢) ⊆ 𝑦) ↔ (𝑥𝑢𝑢 ⊆ (𝐹𝑦))))
4039rexbidva 3049 . . . . . . . . . . 11 (((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ 𝑦𝐾) ∧ 𝐹:𝑋𝑌) ∧ (𝑥 ∈ (𝐹𝑦) ∧ 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥))) → (∃𝑢𝐽 (𝑥𝑢 ∧ (𝐹𝑢) ⊆ 𝑦) ↔ ∃𝑢𝐽 (𝑥𝑢𝑢 ⊆ (𝐹𝑦))))
4128, 40mpbid 222 . . . . . . . . . 10 (((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ 𝑦𝐾) ∧ 𝐹:𝑋𝑌) ∧ (𝑥 ∈ (𝐹𝑦) ∧ 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥))) → ∃𝑢𝐽 (𝑥𝑢𝑢 ⊆ (𝐹𝑦)))
4241expr 643 . . . . . . . . 9 (((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ 𝑦𝐾) ∧ 𝐹:𝑋𝑌) ∧ 𝑥 ∈ (𝐹𝑦)) → (𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥) → ∃𝑢𝐽 (𝑥𝑢𝑢 ⊆ (𝐹𝑦))))
4342ralimdva 2962 . . . . . . . 8 ((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ 𝑦𝐾) ∧ 𝐹:𝑋𝑌) → (∀𝑥 ∈ (𝐹𝑦)𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥) → ∀𝑥 ∈ (𝐹𝑦)∃𝑢𝐽 (𝑥𝑢𝑢 ⊆ (𝐹𝑦))))
4418, 43syld 47 . . . . . . 7 ((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ 𝑦𝐾) ∧ 𝐹:𝑋𝑌) → (∀𝑥𝑋 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥) → ∀𝑥 ∈ (𝐹𝑦)∃𝑢𝐽 (𝑥𝑢𝑢 ⊆ (𝐹𝑦))))
4544impr 649 . . . . . 6 ((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ 𝑦𝐾) ∧ (𝐹:𝑋𝑌 ∧ ∀𝑥𝑋 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥))) → ∀𝑥 ∈ (𝐹𝑦)∃𝑢𝐽 (𝑥𝑢𝑢 ⊆ (𝐹𝑦)))
4645an32s 846 . . . . 5 ((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ (𝐹:𝑋𝑌 ∧ ∀𝑥𝑋 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥))) ∧ 𝑦𝐾) → ∀𝑥 ∈ (𝐹𝑦)∃𝑢𝐽 (𝑥𝑢𝑢 ⊆ (𝐹𝑦)))
47 topontop 20718 . . . . . . 7 (𝐽 ∈ (TopOn‘𝑋) → 𝐽 ∈ Top)
4847ad3antrrr 766 . . . . . 6 ((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ (𝐹:𝑋𝑌 ∧ ∀𝑥𝑋 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥))) ∧ 𝑦𝐾) → 𝐽 ∈ Top)
49 eltop2 20779 . . . . . 6 (𝐽 ∈ Top → ((𝐹𝑦) ∈ 𝐽 ↔ ∀𝑥 ∈ (𝐹𝑦)∃𝑢𝐽 (𝑥𝑢𝑢 ⊆ (𝐹𝑦))))
5048, 49syl 17 . . . . 5 ((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ (𝐹:𝑋𝑌 ∧ ∀𝑥𝑋 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥))) ∧ 𝑦𝐾) → ((𝐹𝑦) ∈ 𝐽 ↔ ∀𝑥 ∈ (𝐹𝑦)∃𝑢𝐽 (𝑥𝑢𝑢 ⊆ (𝐹𝑦))))
5146, 50mpbird 247 . . . 4 ((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ (𝐹:𝑋𝑌 ∧ ∀𝑥𝑋 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥))) ∧ 𝑦𝐾) → (𝐹𝑦) ∈ 𝐽)
5251ralrimiva 2966 . . 3 (((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ (𝐹:𝑋𝑌 ∧ ∀𝑥𝑋 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥))) → ∀𝑦𝐾 (𝐹𝑦) ∈ 𝐽)
531adantr 481 . . 3 (((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ (𝐹:𝑋𝑌 ∧ ∀𝑥𝑋 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥))) → (𝐹 ∈ (𝐽 Cn 𝐾) ↔ (𝐹:𝑋𝑌 ∧ ∀𝑦𝐾 (𝐹𝑦) ∈ 𝐽)))
5412, 52, 53mpbir2and 957 . 2 (((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) ∧ (𝐹:𝑋𝑌 ∧ ∀𝑥𝑋 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥))) → 𝐹 ∈ (𝐽 Cn 𝐾))
5511, 54impbida 877 1 ((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) → (𝐹 ∈ (𝐽 Cn 𝐾) ↔ (𝐹:𝑋𝑌 ∧ ∀𝑥𝑋 𝐹 ∈ ((𝐽 CnP 𝐾)‘𝑥))))
Colors of variables: wff setvar class
Syntax hints:  wi 4  wb 196  wa 384   = wceq 1483  wcel 1990  wral 2912  wrex 2913  wss 3574   cuni 4436  ccnv 5113  dom cdm 5114  cima 5117  Fun wfun 5882   Fn wfn 5883  wf 5884  cfv 5888  (class class class)co 6650  Topctop 20698  TopOnctopon 20715   Cn ccn 21028   CnP ccnp 21029
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1722  ax-4 1737  ax-5 1839  ax-6 1888  ax-7 1935  ax-8 1992  ax-9 1999  ax-10 2019  ax-11 2034  ax-12 2047  ax-13 2246  ax-ext 2602  ax-sep 4781  ax-nul 4789  ax-pow 4843  ax-pr 4906  ax-un 6949
This theorem depends on definitions:  df-bi 197  df-or 385  df-an 386  df-3an 1039  df-tru 1486  df-ex 1705  df-nf 1710  df-sb 1881  df-eu 2474  df-mo 2475  df-clab 2609  df-cleq 2615  df-clel 2618  df-nfc 2753  df-ne 2795  df-ral 2917  df-rex 2918  df-rab 2921  df-v 3202  df-sbc 3436  df-csb 3534  df-dif 3577  df-un 3579  df-in 3581  df-ss 3588  df-nul 3916  df-if 4087  df-pw 4160  df-sn 4178  df-pr 4180  df-op 4184  df-uni 4437  df-iun 4522  df-br 4654  df-opab 4713  df-mpt 4730  df-id 5024  df-xp 5120  df-rel 5121  df-cnv 5122  df-co 5123  df-dm 5124  df-rn 5125  df-res 5126  df-ima 5127  df-iota 5851  df-fun 5890  df-fn 5891  df-f 5892  df-fv 5896  df-ov 6653  df-oprab 6654  df-mpt2 6655  df-1st 7168  df-2nd 7169  df-map 7859  df-topgen 16104  df-top 20699  df-topon 20716  df-cn 21031  df-cnp 21032
This theorem is referenced by:  cncnp2  21085  cnnei  21086  cnconst2  21087  1stccn  21266  ptcn  21430  cnflf  21806  cnfcf  21846  symgtgp  21905  ghmcnp  21918  metcn  22348  txmetcn  22353  cnlimc  23652  dvcn  23684  dvcnvre  23782  psercn  24180  abelth  24195  cxpcn3  24489  cvmlift2lem11  31295  cvmlift2lem12  31296  cvmlift3lem8  31308  ioccncflimc  40098  cncfuni  40099  icccncfext  40100  icocncflimc  40102  cncfiooicclem1  40106  dirkercncflem2  40321  dirkercncflem4  40323  dirkercncf  40324  fourierdlem32  40356  fourierdlem33  40357  fourierdlem62  40385  fourierdlem93  40416  fourierdlem101  40424
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