We discuss, and make partial progress on, the peaceable queens problem, the protagonist of OEIS sequence A250000. Symbolically, we prove that Jubin's construction of two pentagons is at least a local optimum. Numerically, we find the exact numerical optimums for some specific configurations. Our method can be easily applied to more complicated configurations with more parameters.
@article{arxiv.1902.05886,
title = {Numerical and Symbolic Studies of the Peaceable Queens Problem},
author = {Yukun Yao and Doron Zeilberger},
journal= {arXiv preprint arXiv:1902.05886},
year = {2019}
}