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A159448
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Number of n-edge-colorings of the second Blanusa Snark.
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1
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0, 0, 0, 0, 342675456, 13153078605120, 25637821631078400, 9533380086713683200, 1227485144606805073920, 75547606881603808336896, 2700027498853281914634240, 63595142713108801675900800, 1076856076493029796330188800, 13952190527320266709190514240
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OFFSET
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0,5
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COMMENTS
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The second Blanusa Snark is a cubic graph on 18 vertices and 27 edges with edge chromatic number 4.
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LINKS
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Alois P. Heinz, Table of n, a(n) for n = 0..1000
Eric Weisstein's World of Mathematics, Blanusa Snarks
Eric Weisstein's World of Mathematics, Edge Coloring
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.
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FORMULA
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a(n) = n^27 -54*n^26 + ... (see Maple program).
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MAPLE
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a:= n-> n^27 -54*n^26 +1413*n^25 -23868*n^24 +292526*n^23 -2771853*n^22 +21128307*n^21 -133083282*n^20 +706103282*n^19 -3200482928*n^18 +12523602732*n^17 -42639446348*n^16 +127040507554*n^15 -332524010611*n^14 +766396617378*n^13 -1556509608394*n^12 +2783042514579*n^11 -4368658864218*n^10 +5990173216956*n^9 -7117375900060*n^8 +7240708340968*n^7 -6196441690112*n^6 +4345188866816*n^5 -2398700714304*n^4 +976694192256*n^3 -260203292160*n^2 +33894503424*n: seq(a(n), n=0..16);
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CROSSREFS
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Cf. A159300.
Sequence in context: A230085 A204337 A113739 * A316745 A351459 A015381
Adjacent sequences: A159445 A159446 A159447 * A159449 A159450 A159451
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KEYWORD
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nonn
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AUTHOR
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Alois P. Heinz, Apr 11 2009
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STATUS
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approved
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