A063837 Numbers k>3 such that the divisibility tournament on 2..k has an odd determinant.

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.

Links

Table of n, a(n) for n=1..48.

Crossrefs

Positions of odd terms in A057980.

Sequence in context: A102388 A364680 A284065 * A344871 A071125 A193448

Adjacent sequences: A063834 A063835 A063836 * A063838 A063839 A063840

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