

A131649


Number of distinct improper 2coloring of edges for oddorder cyclic graphs.


0



4, 8, 16, 32, 54, 82, 116, 156, 202, 254, 312, 376, 446, 522, 604, 692, 786, 886, 992, 1104, 1222, 1346, 1476, 1612, 1754, 1902, 2056, 2216, 2382, 2554, 2732, 2916, 3106, 3302, 3504, 3712, 3926, 4146, 4372, 4604, 4842, 5086, 5336, 5592, 5854
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OFFSET

3,1


LINKS

Table of n, a(n) for n=3..47.
Index entries for sequences related to colorings


FORMULA

Conjectured g.f.: 4 + (2*x*((x2)^2*x4))/(x1)^3.  Harvey P. Dale, Jul 07 2013
For n>4, a(n) = 3*n^2  17*n + 26 (conjectured).  Ralf Stephan, Jul 08 2013


MATHEMATICA

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}]
Join[{4, 8}, Table[(135n)/2+(3(n1)^2)/4, {n, 7, 91, 2}]] (* Harvey P. Dale, Jul 07 2013 *)


CROSSREFS

Sequence in context: A101434 A048168 A175341 * A003199 A189925 A007096
Adjacent sequences: A131646 A131647 A131648 * A131650 A131651 A131652


KEYWORD

nonn


AUTHOR

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


EXTENSIONS

More terms from Harvey P. Dale, Jul 07 2013


STATUS

approved



