Yun-Yan Chi and Shin-Cheng Mu. Constructing list homomorphisms from proofs. In the 9th Asian Symposium on Programming Languages and Systems (APLAS 2011), LNCS 7078, pages 74-88. [PDF]
A list of numbers is called steep if each element is larger than the sum of elements to its right. It is an example we often use when we talk about tupling. Can we determine the steepness of a list by a list homomorphism?
Back in 2003, my colleagues there were discussing about the third homomorphism theorem — if a function