A007391 Number of strict first-order maximal independent sets in cycle graph. (Formerly M2205)

0, 0, 0, 0, 0, 3, 0, 8, 3, 15, 11, 27, 26, 49, 53, 88, 102, 156, 190, 275, 346, 484, 621, 851, 1105, 1495, 1956, 2625, 3451, 4608, 6076, 8088, 10684, 14195, 18772, 24912, 32967, 43719, 57879, 76723, 101598, 134641, 178321, 236280, 312962, 414644

Offset

1,6

References

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

R. Yanco and A. Bagchi, K-th order maximal independent sets in path and cycle graphs, J. Graph Theory, submitted, 1994.

Links

Table of n, a(n) for n=1..46.

R. Yanco, Letter and Email to N. J. A. Sloane, 1994

Formula

Empirical g.f.: x^6*(x^2-3) / ((x-1)^2*(x+1)^2*(x^3+x^2-1)). - Colin Barker, Mar 29 2014

a(n) = A001608(n) - b(n) where b(1) = 0, b(2*n+1) = 2*n+1, b(2*n) = 2. - Sean A. Irvine, Jan 02 2018

Crossrefs

Cf. A001608.

Sequence in context: A363053 A174474 A317300 * A247668 A359258 A244854

Adjacent sequences: A007388 A007389 A007390 * A007392 A007393 A007394

Keyword

nonn

Author

N. J. A. Sloane, Mira Bernstein

Extensions

More terms from Sean A. Irvine, Jan 02 2018

Status

approved