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%I #4 May 18 2023 23:26:48
%S 4,44,46,48,50,51,52,68,69,77,81,86,87,93,99,100,108,110,118,126,130,
%T 141,161,162,165,168,174,175,184,185,192,201,202,205,209,214,215,217,
%U 218,225,226,230,234,235,244,247,249,250
%N Numbers k>3 such that the divisibility tournament on 2..k has an odd determinant.
%C 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.
%Y Positions of odd terms in A057980.
%K nonn,more
%O 1,1
%A Rebecca A. Winslow (raw5(AT)students.uwf.edu), Aug 21 2001
%E Offset correct, a(1) inserted, and a(22)-a(48) from _Sean A. Irvine_, May 18 2023
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