

A063837


Divisibility tournaments with odd determinants.


0



44, 46, 48, 50, 51, 52, 68, 69, 77, 81, 86, 87, 93, 99, 100, 108, 110, 118, 126, 130
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OFFSET

0,1


COMMENTS

Let n be a positive integer, n>3. Define a tournament on the vertex set {2,3,...n} by: for i< j, i is adjacent to j if i divides j, else, j is adjacent to i and let T(n) be its adjacency matrix. It appears that values of n for which det(T(n)) is odd are rather sparse. Shown above are the n in the range 4...130 for which det(T(n)) is odd.


LINKS

Table of n, a(n) for n=0..19.


CROSSREFS

Cf. A057980.
Sequence in context: A225619 A121610 A254752 * A178755 A182261 A061757
Adjacent sequences: A063834 A063835 A063836 * A063838 A063839 A063840


KEYWORD

nonn


AUTHOR

Rebecca A. Winslow (raw5(AT)students.uwf.edu), Aug 21 2001


STATUS

approved



