Metamath Proof Explorer


Theorem fuccoval

Description: Value of the functor category. (Contributed by Mario Carneiro, 6-Jan-2017)

Ref Expression
Hypotheses fucco.q Q = C FuncCat D
fucco.n N = C Nat D
fucco.a A = Base C
fucco.o · ˙ = comp D
fucco.x ˙ = comp Q
fucco.f φ R F N G
fucco.g φ S G N H
fuccoval.f φ X A
Assertion fuccoval φ S F G ˙ H R X = S X 1 st F X 1 st G X · ˙ 1 st H X R X

Proof

Step Hyp Ref Expression
1 fucco.q Q = C FuncCat D
2 fucco.n N = C Nat D
3 fucco.a A = Base C
4 fucco.o · ˙ = comp D
5 fucco.x ˙ = comp Q
6 fucco.f φ R F N G
7 fucco.g φ S G N H
8 fuccoval.f φ X A
9 1 2 3 4 5 6 7 fucco φ S F G ˙ H R = x A S x 1 st F x 1 st G x · ˙ 1 st H x R x
10 simpr φ x = X x = X
11 10 fveq2d φ x = X 1 st F x = 1 st F X
12 10 fveq2d φ x = X 1 st G x = 1 st G X
13 11 12 opeq12d φ x = X 1 st F x 1 st G x = 1 st F X 1 st G X
14 10 fveq2d φ x = X 1 st H x = 1 st H X
15 13 14 oveq12d φ x = X 1 st F x 1 st G x · ˙ 1 st H x = 1 st F X 1 st G X · ˙ 1 st H X
16 10 fveq2d φ x = X S x = S X
17 10 fveq2d φ x = X R x = R X
18 15 16 17 oveq123d φ x = X S x 1 st F x 1 st G x · ˙ 1 st H x R x = S X 1 st F X 1 st G X · ˙ 1 st H X R X
19 ovexd φ S X 1 st F X 1 st G X · ˙ 1 st H X R X V
20 9 18 8 19 fvmptd φ S F G ˙ H R X = S X 1 st F X 1 st G X · ˙ 1 st H X R X