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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

Timme, Marc; van Bussel, Frank; Fliegner, Denny; Stolzenberg, Sebastian (2009) "Counting complex disordered states by efficient pattern matching: chromatic polynomials and Potts partition functions", New J. Phys. 11 023001, doi: 10.1088/1367-2630/11/2/023001.

Weisstein, Eric W. "Errera Graph".

Weisstein, Eric W. "Chromatic Polynomial".

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

AUTHOR

Alois P. Heinz, Oct 25 2009

STATUS

approved

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Last modified September 18 06:07 EDT 2021. Contains 347509 sequences. (Running on oeis4.)