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A063837
Numbers k>3 such that the divisibility tournament on 2..k has an odd determinant.
0
4, 44, 46, 48, 50, 51, 52, 68, 69, 77, 81, 86, 87, 93, 99, 100, 108, 110, 118, 126, 130, 141, 161, 162, 165, 168, 174, 175, 184, 185, 192, 201, 202, 205, 209, 214, 215, 217, 218, 225, 226, 230, 234, 235, 244, 247, 249, 250
OFFSET
1,1
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.
CROSSREFS
Positions of odd terms in A057980.
Sequence in context: A102388 A364680 A284065 * A344871 A071125 A193448
KEYWORD
nonn,more
AUTHOR
Rebecca A. Winslow (raw5(AT)students.uwf.edu), Aug 21 2001
EXTENSIONS
Offset correct, a(1) inserted, and a(22)-a(48) from Sean A. Irvine, May 18 2023
STATUS
approved