On equalizers in the category of frames with weakly open homomorphisms
We maximize the total height of order ideals in direct products of finitely many finite chains. We also consider several order ideals simultaneously. As a corollary, a shifting property of some integer sequences, including digit sum sequences, is derived.
Through the study of frame congruences, new characterizations of the paracompactness of frames are obtained.
A congruence relation on a 0-distributive lattice is defined such that the quotient lattice is a distributive lattice and the prime spectrum of and of are homeomorphic. Also it is proved that the minimal prime spectrum (maximal spectrum) of is homeomorphic with the minimal prime spectrum (maximal spectrum) of .
In this paper we investigate the system Conv of all sequential convergences on a distributive lattice .