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Number of distinct improper 2-coloring of edges for odd-order cyclic graphs.
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%I #11 Jul 08 2013 04:06:14

%S 4,8,16,32,54,82,116,156,202,254,312,376,446,522,604,692,786,886,992,

%T 1104,1222,1346,1476,1612,1754,1902,2056,2216,2382,2554,2732,2916,

%U 3106,3302,3504,3712,3926,4146,4372,4604,4842,5086,5336,5592,5854

%N Number of distinct improper 2-coloring of edges for odd-order cyclic graphs.

%H <a href="/index/Coi#coloring">Index entries for sequences related to colorings</a>

%F Conjectured g.f.: 4 + (2*x*((x-2)^2*x-4))/(x-1)^3. - _Harvey P. Dale_, Jul 07 2013

%F For n>4, a(n) = 3*n^2 - 17*n + 26 (conjectured). - _Ralf Stephan_, Jul 08 2013

%t Table[If[n == 3, n + 1, If[n == 5, n + 3, 1/2 (13 - 5 n) + 3/4 (-1 + n)^2]], {n, 3, 31, 2}]

%t Join[{4,8},Table[(13-5n)/2+(3(n-1)^2)/4,{n,7,91,2}]] (* _Harvey P. Dale_, Jul 07 2013 *)

%K nonn

%O 3,1

%A M. Razid Black (mrazidblack(AT)hotmail.com), Sep 10 2007

%E More terms from _Harvey P. Dale_, Jul 07 2013