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A057980 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. If T(n) denotes its adjacency matrix, then the above sequence is det(T(n))for n=4,5,6....42. 1
1, 0, 2, 0, 2, -6, 14, 0, 44, 0, 18, -214, 308, 0, 168, 0, 516, -2008, 2328, 0, 14232, -11124, 15552, -29556, 95592, 0, 244464, 0, 250344, -1012558, 1292240, -5809920, 11906420, 0, -5994822, -7669356, 64935420, 0, 40213980 (list; graph; refs; listen; history; internal format)
OFFSET

4,3

COMMENTS

MATLAB program was used to generate the tournament matrices T(n) and evaluate determinants. Obviously det(T(n))=0 if n is prime.

CROSSREFS

Sequence in context: A156815 A175802 A161803 * A081081 A111111 A185343

Adjacent sequences:  A057977 A057978 A057979 * A057981 A057982 A057983

KEYWORD

sign

AUTHOR

Rohan Hemasinha (rhemasin(AT)uwf.edu), Nov 27 2000

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Last modified February 17 12:38 EST 2012. Contains 206021 sequences.