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 A166964 Number of n-colorings of the Errera graph. 2
 0, 0, 0, 0, 960, 4669200, 1342968480, 96351366720, 2967164565120, 51747096270240, 600189633086400, 5123179804311360, 34443698001387840, 191288688014664240, 908558913657114720, 3788089202221833600, 14145018198653072640, 48056437943548695360 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,5 COMMENTS The Errera graph is a planar graph on 17 vertices and 45 edges with 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 023001 (2009). Eric Weisstein's World of Mathematics, Errera Graph. Eric Weisstein's World of Mathematics, Chromatic Polynomial. Index entries for linear recurrences with constant coefficients, signature (18, -153, 816, -3060, 8568, -18564, 31824, -43758, 48620, -43758, 31824, -18564, 8568, -3060, 816, -153, 18, -1). FORMULA a(n) = n^17 - 45*n^16 + ... (see Maple program). MAPLE a:= n-> n^17 -45*n^16 +960*n^15 -12900*n^14 +122327*n^13 -868834*n^12 +4785355*n^11 -20863215*n^10 +72791543*n^9 -203886157*n^8 +456534224*n^7 -807157880*n^6 +1101393064*n^5 -1116652249*n^4 +788961246*n^3 -344673280*n^2 +69525840*n: seq(a(n), n=0..20); MATHEMATICA a[n_] := n^17 - 45*n^16 + 960*n^15 - 12900*n^14 + 122327*n^13 - 868834*n^12 + 4785355*n^11 - 20863215*n^10 + 72791543*n^9 - 203886157*n^8 + 456534224*n^7 - 807157880*n^6 + 1101393064*n^5 - 1116652249*n^4 + 788961246*n^3 - 344673280*n^2 + 69525840*n; Table[a[n], {n, 0, 10}] (* G. C. Greubel, May 29 2016 *) CROSSREFS Sequence in context: A278011 A282012 A147883 * A316337 A274120 A063797 Adjacent sequences: A166961 A166962 A166963 * A166965 A166966 A166967 KEYWORD nonn,easy AUTHOR Alois P. Heinz, Oct 25 2009 STATUS approved

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Last modified May 27 02:22 EDT 2024. Contains 372847 sequences. (Running on oeis4.)