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A141348
Number of extreme n-breakable vectors.
2
1, 2, 3, 6, 8, 16, 22, 37, 53, 92, 110, 201, 260, 376, 519, 831, 963, 1592, 1837, 2692, 3593, 5298, 5693, 8921, 11044, 14664, 17689, 26479, 27298, 43387
OFFSET
3,2
COMMENTS
An n-breakable vector is a vector v=(v(1),v(2),...,v(n-2)) such that each v(i) is a nonnegative integer and SUM i*v(i) == 1 (mod n-1).
Extreme n-breakable vectors form the set of n-breakable vectors such that every n-breakable vector component-wise dominates some vector from this set, but no two distinct vectors from this set dominate one another.
Number of vectors from the Hilbert basis in A141347 with the first coordinate equal 1.
LINKS
Max A. Alekseyev and Pavel A. Pevzner, "Multi-Break Rearrangements and Chromosomal Evolution". Theoretical Computer Science 395(2-3) (2008), pp. 193-202.
EXAMPLE
The set of extreme 6-breakable vectors is { (1,0,0,0), (0,0,2,0), (0,1,0,1), (0,0,1,2), (0,3,0,0), (0,0,0,4) }.
CROSSREFS
Sequence in context: A267007 A091070 A133586 * A334269 A029867 A056348
KEYWORD
nonn,more
AUTHOR
Max Alekseyev, Jun 27 2008
EXTENSIONS
a(21)-a(32) from Max Alekseyev, Sep 16 2011
STATUS
approved