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Theorem insubm 18916
Description: The intersection of two submonoids is a submonoid. (Contributed by AV, 25-Feb-2024.)
Assertion
Ref Expression
insubm ((𝐴 ∈ (SubMnd‘𝑀) ∧ 𝐵 ∈ (SubMnd‘𝑀)) → (𝐴𝐵) ∈ (SubMnd‘𝑀))

Proof of Theorem insubm
Dummy variables 𝑎 𝑏 𝑥 𝑦 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 submrcl 18899 . . 3 (𝐴 ∈ (SubMnd‘𝑀) → 𝑀 ∈ Mnd)
2 ssinss1 4198 . . . . . . . . 9 (𝐴 ⊆ (Base‘𝑀) → (𝐴𝐵) ⊆ (Base‘𝑀))
323ad2ant1 1151 . . . . . . . 8 ((𝐴 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐴 ∧ ∀𝑎𝐴𝑏𝐴 (𝑎(+g𝑀)𝑏) ∈ 𝐴) → (𝐴𝐵) ⊆ (Base‘𝑀))
43ad2antrl 741 . . . . . . 7 ((𝑀 ∈ Mnd ∧ ((𝐴 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐴 ∧ ∀𝑎𝐴𝑏𝐴 (𝑎(+g𝑀)𝑏) ∈ 𝐴) ∧ (𝐵 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐵 ∧ ∀𝑎𝐵𝑏𝐵 (𝑎(+g𝑀)𝑏) ∈ 𝐵))) → (𝐴𝐵) ⊆ (Base‘𝑀))
5 elin 3922 . . . . . . . . . . . . 13 ((0g𝑀) ∈ (𝐴𝐵) ↔ ((0g𝑀) ∈ 𝐴 ∧ (0g𝑀) ∈ 𝐵))
65simplbi2com 508 . . . . . . . . . . . 12 ((0g𝑀) ∈ 𝐵 → ((0g𝑀) ∈ 𝐴 → (0g𝑀) ∈ (𝐴𝐵)))
763ad2ant2 1152 . . . . . . . . . . 11 ((𝐵 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐵 ∧ ∀𝑎𝐵𝑏𝐵 (𝑎(+g𝑀)𝑏) ∈ 𝐵) → ((0g𝑀) ∈ 𝐴 → (0g𝑀) ∈ (𝐴𝐵)))
87com12 33 . . . . . . . . . 10 ((0g𝑀) ∈ 𝐴 → ((𝐵 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐵 ∧ ∀𝑎𝐵𝑏𝐵 (𝑎(+g𝑀)𝑏) ∈ 𝐵) → (0g𝑀) ∈ (𝐴𝐵)))
983ad2ant2 1152 . . . . . . . . 9 ((𝐴 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐴 ∧ ∀𝑎𝐴𝑏𝐴 (𝑎(+g𝑀)𝑏) ∈ 𝐴) → ((𝐵 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐵 ∧ ∀𝑎𝐵𝑏𝐵 (𝑎(+g𝑀)𝑏) ∈ 𝐵) → (0g𝑀) ∈ (𝐴𝐵)))
109imp 412 . . . . . . . 8 (((𝐴 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐴 ∧ ∀𝑎𝐴𝑏𝐴 (𝑎(+g𝑀)𝑏) ∈ 𝐴) ∧ (𝐵 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐵 ∧ ∀𝑎𝐵𝑏𝐵 (𝑎(+g𝑀)𝑏) ∈ 𝐵)) → (0g𝑀) ∈ (𝐴𝐵))
1110adantl 487 . . . . . . 7 ((𝑀 ∈ Mnd ∧ ((𝐴 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐴 ∧ ∀𝑎𝐴𝑏𝐴 (𝑎(+g𝑀)𝑏) ∈ 𝐴) ∧ (𝐵 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐵 ∧ ∀𝑎𝐵𝑏𝐵 (𝑎(+g𝑀)𝑏) ∈ 𝐵))) → (0g𝑀) ∈ (𝐴𝐵))
12 elin 3922 . . . . . . . . . 10 (𝑥 ∈ (𝐴𝐵) ↔ (𝑥𝐴𝑥𝐵))
13 elin 3922 . . . . . . . . . 10 (𝑦 ∈ (𝐴𝐵) ↔ (𝑦𝐴𝑦𝐵))
1412, 13anbi12i 640 . . . . . . . . 9 ((𝑥 ∈ (𝐴𝐵) ∧ 𝑦 ∈ (𝐴𝐵)) ↔ ((𝑥𝐴𝑥𝐵) ∧ (𝑦𝐴𝑦𝐵)))
15 oveq1 7426 . . . . . . . . . . . . . . . . 17 (𝑎 = 𝑥 → (𝑎(+g𝑀)𝑏) = (𝑥(+g𝑀)𝑏))
1615eleq1d 2850 . . . . . . . . . . . . . . . 16 (𝑎 = 𝑥 → ((𝑎(+g𝑀)𝑏) ∈ 𝐴 ↔ (𝑥(+g𝑀)𝑏) ∈ 𝐴))
17 oveq2 7427 . . . . . . . . . . . . . . . . 17 (𝑏 = 𝑦 → (𝑥(+g𝑀)𝑏) = (𝑥(+g𝑀)𝑦))
1817eleq1d 2850 . . . . . . . . . . . . . . . 16 (𝑏 = 𝑦 → ((𝑥(+g𝑀)𝑏) ∈ 𝐴 ↔ (𝑥(+g𝑀)𝑦) ∈ 𝐴))
19 simpl 488 . . . . . . . . . . . . . . . . 17 ((𝑥𝐴𝑥𝐵) → 𝑥𝐴)
2019adantr 486 . . . . . . . . . . . . . . . 16 (((𝑥𝐴𝑥𝐵) ∧ (𝑦𝐴𝑦𝐵)) → 𝑥𝐴)
21 eqidd 2766 . . . . . . . . . . . . . . . 16 ((((𝑥𝐴𝑥𝐵) ∧ (𝑦𝐴𝑦𝐵)) ∧ 𝑎 = 𝑥) → 𝐴 = 𝐴)
22 simpl 488 . . . . . . . . . . . . . . . . 17 ((𝑦𝐴𝑦𝐵) → 𝑦𝐴)
2322adantl 487 . . . . . . . . . . . . . . . 16 (((𝑥𝐴𝑥𝐵) ∧ (𝑦𝐴𝑦𝐵)) → 𝑦𝐴)
2416, 18, 20, 21, 23rspc2vd 3902 . . . . . . . . . . . . . . 15 (((𝑥𝐴𝑥𝐵) ∧ (𝑦𝐴𝑦𝐵)) → (∀𝑎𝐴𝑏𝐴 (𝑎(+g𝑀)𝑏) ∈ 𝐴 → (𝑥(+g𝑀)𝑦) ∈ 𝐴))
2524com12 33 . . . . . . . . . . . . . 14 (∀𝑎𝐴𝑏𝐴 (𝑎(+g𝑀)𝑏) ∈ 𝐴 → (((𝑥𝐴𝑥𝐵) ∧ (𝑦𝐴𝑦𝐵)) → (𝑥(+g𝑀)𝑦) ∈ 𝐴))
26253ad2ant3 1153 . . . . . . . . . . . . 13 ((𝐴 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐴 ∧ ∀𝑎𝐴𝑏𝐴 (𝑎(+g𝑀)𝑏) ∈ 𝐴) → (((𝑥𝐴𝑥𝐵) ∧ (𝑦𝐴𝑦𝐵)) → (𝑥(+g𝑀)𝑦) ∈ 𝐴))
2726ad2antrl 741 . . . . . . . . . . . 12 ((𝑀 ∈ Mnd ∧ ((𝐴 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐴 ∧ ∀𝑎𝐴𝑏𝐴 (𝑎(+g𝑀)𝑏) ∈ 𝐴) ∧ (𝐵 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐵 ∧ ∀𝑎𝐵𝑏𝐵 (𝑎(+g𝑀)𝑏) ∈ 𝐵))) → (((𝑥𝐴𝑥𝐵) ∧ (𝑦𝐴𝑦𝐵)) → (𝑥(+g𝑀)𝑦) ∈ 𝐴))
2827imp 412 . . . . . . . . . . 11 (((𝑀 ∈ Mnd ∧ ((𝐴 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐴 ∧ ∀𝑎𝐴𝑏𝐴 (𝑎(+g𝑀)𝑏) ∈ 𝐴) ∧ (𝐵 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐵 ∧ ∀𝑎𝐵𝑏𝐵 (𝑎(+g𝑀)𝑏) ∈ 𝐵))) ∧ ((𝑥𝐴𝑥𝐵) ∧ (𝑦𝐴𝑦𝐵))) → (𝑥(+g𝑀)𝑦) ∈ 𝐴)
2915eleq1d 2850 . . . . . . . . . . . . . . . . 17 (𝑎 = 𝑥 → ((𝑎(+g𝑀)𝑏) ∈ 𝐵 ↔ (𝑥(+g𝑀)𝑏) ∈ 𝐵))
3017eleq1d 2850 . . . . . . . . . . . . . . . . 17 (𝑏 = 𝑦 → ((𝑥(+g𝑀)𝑏) ∈ 𝐵 ↔ (𝑥(+g𝑀)𝑦) ∈ 𝐵))
31 simpr 490 . . . . . . . . . . . . . . . . . 18 ((𝑥𝐴𝑥𝐵) → 𝑥𝐵)
3231adantr 486 . . . . . . . . . . . . . . . . 17 (((𝑥𝐴𝑥𝐵) ∧ (𝑦𝐴𝑦𝐵)) → 𝑥𝐵)
33 eqidd 2766 . . . . . . . . . . . . . . . . 17 ((((𝑥𝐴𝑥𝐵) ∧ (𝑦𝐴𝑦𝐵)) ∧ 𝑎 = 𝑥) → 𝐵 = 𝐵)
34 simpr 490 . . . . . . . . . . . . . . . . . 18 ((𝑦𝐴𝑦𝐵) → 𝑦𝐵)
3534adantl 487 . . . . . . . . . . . . . . . . 17 (((𝑥𝐴𝑥𝐵) ∧ (𝑦𝐴𝑦𝐵)) → 𝑦𝐵)
3629, 30, 32, 33, 35rspc2vd 3902 . . . . . . . . . . . . . . . 16 (((𝑥𝐴𝑥𝐵) ∧ (𝑦𝐴𝑦𝐵)) → (∀𝑎𝐵𝑏𝐵 (𝑎(+g𝑀)𝑏) ∈ 𝐵 → (𝑥(+g𝑀)𝑦) ∈ 𝐵))
3736com12 33 . . . . . . . . . . . . . . 15 (∀𝑎𝐵𝑏𝐵 (𝑎(+g𝑀)𝑏) ∈ 𝐵 → (((𝑥𝐴𝑥𝐵) ∧ (𝑦𝐴𝑦𝐵)) → (𝑥(+g𝑀)𝑦) ∈ 𝐵))
38373ad2ant3 1153 . . . . . . . . . . . . . 14 ((𝐵 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐵 ∧ ∀𝑎𝐵𝑏𝐵 (𝑎(+g𝑀)𝑏) ∈ 𝐵) → (((𝑥𝐴𝑥𝐵) ∧ (𝑦𝐴𝑦𝐵)) → (𝑥(+g𝑀)𝑦) ∈ 𝐵))
3938adantl 487 . . . . . . . . . . . . 13 (((𝐴 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐴 ∧ ∀𝑎𝐴𝑏𝐴 (𝑎(+g𝑀)𝑏) ∈ 𝐴) ∧ (𝐵 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐵 ∧ ∀𝑎𝐵𝑏𝐵 (𝑎(+g𝑀)𝑏) ∈ 𝐵)) → (((𝑥𝐴𝑥𝐵) ∧ (𝑦𝐴𝑦𝐵)) → (𝑥(+g𝑀)𝑦) ∈ 𝐵))
4039adantl 487 . . . . . . . . . . . 12 ((𝑀 ∈ Mnd ∧ ((𝐴 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐴 ∧ ∀𝑎𝐴𝑏𝐴 (𝑎(+g𝑀)𝑏) ∈ 𝐴) ∧ (𝐵 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐵 ∧ ∀𝑎𝐵𝑏𝐵 (𝑎(+g𝑀)𝑏) ∈ 𝐵))) → (((𝑥𝐴𝑥𝐵) ∧ (𝑦𝐴𝑦𝐵)) → (𝑥(+g𝑀)𝑦) ∈ 𝐵))
4140imp 412 . . . . . . . . . . 11 (((𝑀 ∈ Mnd ∧ ((𝐴 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐴 ∧ ∀𝑎𝐴𝑏𝐴 (𝑎(+g𝑀)𝑏) ∈ 𝐴) ∧ (𝐵 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐵 ∧ ∀𝑎𝐵𝑏𝐵 (𝑎(+g𝑀)𝑏) ∈ 𝐵))) ∧ ((𝑥𝐴𝑥𝐵) ∧ (𝑦𝐴𝑦𝐵))) → (𝑥(+g𝑀)𝑦) ∈ 𝐵)
4228, 41elind 4153 . . . . . . . . . 10 (((𝑀 ∈ Mnd ∧ ((𝐴 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐴 ∧ ∀𝑎𝐴𝑏𝐴 (𝑎(+g𝑀)𝑏) ∈ 𝐴) ∧ (𝐵 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐵 ∧ ∀𝑎𝐵𝑏𝐵 (𝑎(+g𝑀)𝑏) ∈ 𝐵))) ∧ ((𝑥𝐴𝑥𝐵) ∧ (𝑦𝐴𝑦𝐵))) → (𝑥(+g𝑀)𝑦) ∈ (𝐴𝐵))
4342ex 418 . . . . . . . . 9 ((𝑀 ∈ Mnd ∧ ((𝐴 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐴 ∧ ∀𝑎𝐴𝑏𝐴 (𝑎(+g𝑀)𝑏) ∈ 𝐴) ∧ (𝐵 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐵 ∧ ∀𝑎𝐵𝑏𝐵 (𝑎(+g𝑀)𝑏) ∈ 𝐵))) → (((𝑥𝐴𝑥𝐵) ∧ (𝑦𝐴𝑦𝐵)) → (𝑥(+g𝑀)𝑦) ∈ (𝐴𝐵)))
4414, 43biimtrid 245 . . . . . . . 8 ((𝑀 ∈ Mnd ∧ ((𝐴 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐴 ∧ ∀𝑎𝐴𝑏𝐴 (𝑎(+g𝑀)𝑏) ∈ 𝐴) ∧ (𝐵 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐵 ∧ ∀𝑎𝐵𝑏𝐵 (𝑎(+g𝑀)𝑏) ∈ 𝐵))) → ((𝑥 ∈ (𝐴𝐵) ∧ 𝑦 ∈ (𝐴𝐵)) → (𝑥(+g𝑀)𝑦) ∈ (𝐴𝐵)))
4544ralrimivv 3208 . . . . . . 7 ((𝑀 ∈ Mnd ∧ ((𝐴 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐴 ∧ ∀𝑎𝐴𝑏𝐴 (𝑎(+g𝑀)𝑏) ∈ 𝐴) ∧ (𝐵 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐵 ∧ ∀𝑎𝐵𝑏𝐵 (𝑎(+g𝑀)𝑏) ∈ 𝐵))) → ∀𝑥 ∈ (𝐴𝐵)∀𝑦 ∈ (𝐴𝐵)(𝑥(+g𝑀)𝑦) ∈ (𝐴𝐵))
464, 11, 453jca 1146 . . . . . 6 ((𝑀 ∈ Mnd ∧ ((𝐴 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐴 ∧ ∀𝑎𝐴𝑏𝐴 (𝑎(+g𝑀)𝑏) ∈ 𝐴) ∧ (𝐵 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐵 ∧ ∀𝑎𝐵𝑏𝐵 (𝑎(+g𝑀)𝑏) ∈ 𝐵))) → ((𝐴𝐵) ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ (𝐴𝐵) ∧ ∀𝑥 ∈ (𝐴𝐵)∀𝑦 ∈ (𝐴𝐵)(𝑥(+g𝑀)𝑦) ∈ (𝐴𝐵)))
4746ex 418 . . . . 5 (𝑀 ∈ Mnd → (((𝐴 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐴 ∧ ∀𝑎𝐴𝑏𝐴 (𝑎(+g𝑀)𝑏) ∈ 𝐴) ∧ (𝐵 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐵 ∧ ∀𝑎𝐵𝑏𝐵 (𝑎(+g𝑀)𝑏) ∈ 𝐵)) → ((𝐴𝐵) ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ (𝐴𝐵) ∧ ∀𝑥 ∈ (𝐴𝐵)∀𝑦 ∈ (𝐴𝐵)(𝑥(+g𝑀)𝑦) ∈ (𝐴𝐵))))
48 eqid 2765 . . . . . . 7 (Base‘𝑀) = (Base‘𝑀)
49 eqid 2765 . . . . . . 7 (0g𝑀) = (0g𝑀)
50 eqid 2765 . . . . . . 7 (+g𝑀) = (+g𝑀)
5148, 49, 50issubm 18900 . . . . . 6 (𝑀 ∈ Mnd → (𝐴 ∈ (SubMnd‘𝑀) ↔ (𝐴 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐴 ∧ ∀𝑎𝐴𝑏𝐴 (𝑎(+g𝑀)𝑏) ∈ 𝐴)))
5248, 49, 50issubm 18900 . . . . . 6 (𝑀 ∈ Mnd → (𝐵 ∈ (SubMnd‘𝑀) ↔ (𝐵 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐵 ∧ ∀𝑎𝐵𝑏𝐵 (𝑎(+g𝑀)𝑏) ∈ 𝐵)))
5351, 52anbi12d 644 . . . . 5 (𝑀 ∈ Mnd → ((𝐴 ∈ (SubMnd‘𝑀) ∧ 𝐵 ∈ (SubMnd‘𝑀)) ↔ ((𝐴 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐴 ∧ ∀𝑎𝐴𝑏𝐴 (𝑎(+g𝑀)𝑏) ∈ 𝐴) ∧ (𝐵 ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ 𝐵 ∧ ∀𝑎𝐵𝑏𝐵 (𝑎(+g𝑀)𝑏) ∈ 𝐵))))
5448, 49, 50issubm 18900 . . . . 5 (𝑀 ∈ Mnd → ((𝐴𝐵) ∈ (SubMnd‘𝑀) ↔ ((𝐴𝐵) ⊆ (Base‘𝑀) ∧ (0g𝑀) ∈ (𝐴𝐵) ∧ ∀𝑥 ∈ (𝐴𝐵)∀𝑦 ∈ (𝐴𝐵)(𝑥(+g𝑀)𝑦) ∈ (𝐴𝐵))))
5547, 53, 543imtr4d 297 . . . 4 (𝑀 ∈ Mnd → ((𝐴 ∈ (SubMnd‘𝑀) ∧ 𝐵 ∈ (SubMnd‘𝑀)) → (𝐴𝐵) ∈ (SubMnd‘𝑀)))
5655expd 421 . . 3 (𝑀 ∈ Mnd → (𝐴 ∈ (SubMnd‘𝑀) → (𝐵 ∈ (SubMnd‘𝑀) → (𝐴𝐵) ∈ (SubMnd‘𝑀))))
571, 56mpcom 39 . 2 (𝐴 ∈ (SubMnd‘𝑀) → (𝐵 ∈ (SubMnd‘𝑀) → (𝐴𝐵) ∈ (SubMnd‘𝑀)))
5857imp 412 1 ((𝐴 ∈ (SubMnd‘𝑀) ∧ 𝐵 ∈ (SubMnd‘𝑀)) → (𝐴𝐵) ∈ (SubMnd‘𝑀))
Colors of variables:    wff setvar class
This proof depends on syntax axioms:  wi 4  wa 401  w3a 1103  wcel 2146  wral 3081  cin 3905  wss 3906  cfv 6540  (class class class)co 7419  Basecbs 17293  +gcplusg 17334  0gc0g 17516  Mndcmnd 18826  SubMndcsubmnd 18879
This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1943  ax-6 2000  ax-7 2041  ax-8 2148  ax-9 2156  ax-10 2179  ax-11 2195  ax-12 2216  ax-ext 2737  ax-sep 5259  ax-nul 5271  ax-pow 5338  ax-pr 5406
This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1813  df-nf 1817  df-sb 2100  df-mo 2569  df-eu 2599  df-clab 2744  df-cleq 2757  df-clel 2840  df-nfc 2914  df-ne 2961  df-ral 3082  df-rex 3092  df-rab 3419  df-v 3459  df-sbc 3747  df-csb 3855  df-dif 3909  df-un 3911  df-in 3913  df-ss 3923  df-nul 4287  df-if 4490  df-pw 4566  df-sn 4592  df-pr 4594  df-op 4598  df-uni 4875  df-br 5112  df-opab 5176  df-mpt 5195  df-id 5558  df-xp 5669  df-rel 5670  df-cnv 5671  df-co 5672  df-dm 5673  df-rn 5674  df-res 5675  df-ima 5676  df-iota 6496  df-fun 6542  df-fv 6548  df-ov 7422  df-submnd 18881
This theorem is used by:  symgsubmefmnd  19514
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