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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 (list; graph; refs; listen; history; text; internal format)



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.


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


Cf. A057980.

Sequence in context: A225619 A121610 A254752 * A178755 A182261 A061757

Adjacent sequences:  A063834 A063835 A063836 * A063838 A063839 A063840




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



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Last modified December 2 10:39 EST 2020. Contains 338876 sequences. (Running on oeis4.)