OFFSET
0,5
COMMENTS
The Flower Snark J_5 is a cubic graph on 20 vertices and 30 edges with edge chromatic number 4.
LINKS
Alois P. Heinz, Table of n, a(n) for n = 0..1000
Marc Timme, Frank van Bussel, Denny Fliegner, and Sebastian Stolzenberg, Counting complex disordered states by efficient pattern matching: chromatic polynomials and Potts partition functions, New J. Phys. 11 (2009), 023001.
Eric Weisstein's World of Mathematics, Edge Coloring.
Eric Weisstein's World of Mathematics, Flower Snark.
Index entries for linear recurrences with constant coefficients, signature (31, -465, 4495, -31465, 169911, -736281, 2629575, -7888725, 20160075, -44352165, 84672315, -141120525, 206253075, -265182525, 300540195, -300540195, 265182525, -206253075, 141120525, -84672315, 44352165, -20160075, 7888725, -2629575, 736281, -169911, 31465, -4495, 465, -31, 1).
FORMULA
a(n) = n^30 -60*n^29 + ... (see Maple program).
MAPLE
a:= n-> n^30 -60*n^29 +1750*n^28 -33060*n^27 +454764*n^26 -4854961*n^25 +41867565*n^24 -299720670*n^23 +1816540880*n^22 -9459103458*n^21 +42798016565*n^20 -169732938235*n^19 +594070747635*n^18 -1844689245281*n^17 +5101859382634*n^16 -12602061696493*n^15 +27845262245640*n^14 -55059880972850*n^13 +97345025180086*n^12 -153519740823868*n^11 +215073243442384*n^10 -265950300198200*n^9 +287573130360800*n^8 -268312812840064*n^7 +211957175072256*n^6 -137938984061952*n^5 +70986108216320*n^4 -27050740894720*n^3 +6769804881920*n^2 -831629027328*n: seq(a(n), n=0..13);
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Alois P. Heinz, Apr 09 2009
STATUS
approved