theorem instBigCoffeeChainAtToParent
theorem instBigCoffeeChainAtToParent: ∀ (x t : Type) [BigCoffeeChain.At x t], CoffeeChain.At x t
theorem instBigCoffeeChainAtToParent
theorem instBigCoffeeChainAtToParent: ∀ (x t : Type) [BigCoffeeChain.At x t], CoffeeChain.At x t