

A007383


Number of strict firstorder maximal independent sets in path graph.
(Formerly M2228)


0



0, 0, 1, 0, 3, 1, 6, 4, 11, 10, 20, 21, 36, 41, 64, 77, 113, 141, 199, 254, 350, 453, 615, 803, 1080, 1418, 1896, 2498, 3328, 4394, 5841, 7722, 10251, 13563, 17990, 23814, 31571, 41804, 55404, 73375, 97228, 128779, 170624, 226007, 299425
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OFFSET

1,5


REFERENCES

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
R. Yanco and A. Bagchi, Kth order maximal independent sets in path and cycle graphs, J. Graph Theory, submitted, 1994.


LINKS

Table of n, a(n) for n=1..45.
R. Yanco, Letter and Email to N. J. A. Sloane, 1994


FORMULA

Empirical g.f.: x^3 / ((x1)^2*(x+1)^2*(x^3+x^21)).  Colin Barker, Mar 29 2014
a(n) = A000931(n + 6)  b(n) where b(2*n+1) = 1 and b(2*n) = n+1.  Sean A. Irvine, Jan 02 2018


CROSSREFS

Cf. A000931.
Sequence in context: A127754 A328508 A210841 * A206434 A120394 A016575
Adjacent sequences: A007380 A007381 A007382 * A007384 A007385 A007386


KEYWORD

nonn


AUTHOR

N. J. A. Sloane, Mira Bernstein


EXTENSIONS

More terms from Sean A. Irvine, Jan 02 2018


STATUS

approved



