VOOZH about

URL: https://oeis.org/A007380

⇱ A007380 - OEIS

login
A007380
Number of 5th-order maximal independent sets in path graph.
22
1, 2, 1, 3, 1, 4, 2, 5, 4, 6, 7, 7, 11, 9, 16, 13, 22, 20, 29, 31, 38, 47, 51, 69, 71, 98, 102, 136, 149, 187, 218, 258, 316, 360, 452, 509, 639, 727, 897, 1043, 1257, 1495, 1766, 2134, 2493, 3031, 3536, 4288, 5031, 6054, 7165, 8547, 10196
OFFSET
1,2
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
R. Yanco and A. Bagchi, K-th order maximal independent sets in path and cycle graphs, Unpublished manuscript, 1994. (Annotated scanned copy)
FORMULA
Apparently, a(n) = a(n-2) + a(n-7) with g.f. -x*(1+2*x+x^3+x^5+x^6)/(-1+x^2+x^7). - R. J. Mathar, Oct 30 2009
a(n) = T(2, 7, n + 7) where T(a, b, n) = Sum_{a*x+b*y = n, x >= 0, y >= 0} binomial(x+y, y). - Sean A. Irvine, Jan 02 2018
CROSSREFS
Sequence in context: A246582 A059499 A113322 * A369813 A394675 A319162
KEYWORD
nonn
EXTENSIONS
More terms from Sean A. Irvine, Jan 02 2018
STATUS
approved