%I #10 Dec 23 2017 00:12:01
%S 1,-24,260,-1670,6999,-19698,36408,-40240,20170
%N List of coefficients of reduced chromatic polynomial of icosahedron, highest order terms first.
%C These are the coefficients when the chromatic polynomial of the icosahedron (see A296917) is divided by x*(x-1)*(x-2)*(x-3).
%D N. Biggs, Algebraic Graph Theory, 2nd ed. Cambridge University Press, 1993. See p. 69.
%e The reduced chromatic polynomial is x^8-24*x^7+260*x^6-1670*x^5+6999*x^4-19698*x^3+36408*x^2-40240*x+20170.
%e Multiplying by x*(x-1)*(x-2)*(x-3) and expanding we get the chromatic polynomial for the icosahedron, which is x^12 - 30*x^11 + 415*x^10 - 3500*x^9 + 20023*x^8 - 81622*x^7 + 241605*x^6 - 517360*x^5 + 780286*x^4 - 782108*x^3 + 463310*x^2 - 121020*x.
%Y Cf. A296917, A218514.
%K sign,fini,full
%O 1,2
%A _N. J. A. Sloane_, Dec 22 2017