Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A007382
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A007382 Number of strict (-1)st-order maximal independent sets in path graph.
(Formerly M2365)
+0
2
0, 0, 3, 4, 11, 16, 32, 49, 87, 137, 231, 369, 608, 978, 1595, 2574, 4179, 6754, 10944, 17699, 28655, 46355, 75023, 121379, 196416, 317796, 514227, 832024, 1346267 (list; graph; listen)
OFFSET

1,3

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.

FORMULA

John W. Layman (layman(AT)math.vt.edu) observes that if b(n)=1+A007382(n) then b(n) = b(n-1) + 3b(n-2) - 2b(n-3) - 3b(n-4) + b(n-5) + b(n-6) for all 27 terms shown.

G.f.: [x^3(x^3+2x^2-x-3)]/[(1-x-x^2)*(1-x^2)^2].

CROSSREFS

Equals A054451(n+1) - 1.

Sequence in context: A041020 A041527 A001641 this_sequence A127804 A027306 A026676

Adjacent sequences: A007379 A007380 A007381 this_sequence A007383 A007384 A007385

KEYWORD

nonn

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com), Mira Bernstein

page 1

Search completed in 0.002 seconds

Lookup | Welcome | Find friends | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
More pages | Superseeker | Maintained by N. J. A. Sloane (njas@research.att.com)

Last modified November 24 19:42 EST 2009. Contains 167435 sequences.


AT&T Labs Research