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A301771
Number of odd chordless cycles in the n-Andrásfai graph.
1
0, 1, 8, 33, 100, 255, 584, 1242, 2496, 4785, 8800, 15587, 26676, 44239, 71280, 111860, 171360, 256785, 377112, 543685, 770660, 1075503, 1479544, 2008590, 2693600, 3571425, 4685616, 6087303, 7836148, 10001375, 12662880, 15912424, 19854912, 24609761, 30312360
OFFSET
1,3
COMMENTS
a(11) - a(35) were computed from the definition, not from the conjectured formula. - Pontus von Brömssen, Oct 09 2022
LINKS
Eric Weisstein's World of Mathematics, Andrásfai Graph.
Eric Weisstein's World of Mathematics, Chordless Cycle.
Wikipedia, Andrásfai graph.
R. J. Mathar, Illustrations
FORMULA
Conjectured g.f.: x*(x - 3*x^3 + 4*x^4 + x^5)/(1 - x)^8.
CROSSREFS
Cf. A234602.
Sequence in context: A070736 A051836 A278670 * A070051 A087235 A222346
KEYWORD
nonn
AUTHOR
Eric W. Weisstein, Mar 26 2018
EXTENSIONS
a(8)-a(10) from Andrew Howroyd, Mar 26 2018
a(11)-a(35) from Pontus von Brömssen, Oct 09 2022
Removed program that was based on the conjectured generating function. - N. J. A. Sloane, Feb 09 2024
STATUS
approved