color polynomial

https://im.snibgo.com/col2mp.htm

https://www.whitman.edu/Documents/Academics/Mathematics/fouts.pdf

http://mathworld.wolfram.com/ChromaticPolynomial.html

http://www-math.ucdenver.edu/~wcherowi/courses/m4408/gtln6.htm

https://arxiv.org/abs/cond-mat/0304558

https://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=7047834