

A141348


Number of extreme nbreakable 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
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OFFSET

3,2


COMMENTS

An nbreakable vector is a vector v=(v(1),v(2),...,v(n2)) such that each v(i) is a nonnegative integer and SUM i*v(i) == 1 (mod n1).
Extreme nbreakable vectors form the set of nbreakable vectors such that every nbreakable vector componentwise 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

Table of n, a(n) for n=3..32.
Max A. Alekseyev and Pavel A. Pevzner, "MultiBreak Rearrangements and Chromosomal Evolution". Theoretical Computer Science 395(23) (2008), pp. 193202.


EXAMPLE

The set of extreme 6breakable 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

Cf. A141347, A141349.
Sequence in context: A267007 A091070 A133586 * A334269 A029867 A056348
Adjacent sequences: A141345 A141346 A141347 * A141349 A141350 A141351


KEYWORD

nonn,more


AUTHOR

Max Alekseyev, Jun 27 2008


EXTENSIONS

a(21)a(32) from Max Alekseyev, Sep 16 2011


STATUS

approved



