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A111485
Number of (-1,0,1) periodic irreducible matrices up to sign change, transposition and mirroring over the antidiagonal.
1
1, 3, 12, 107, 951, 10923
OFFSET
1,2
COMMENTS
"Irreducible" is intended to mean "not factoring into blocks along the diagonal". The periods for n=6 are 396 times period 3, 2939 times period 4, 1684 times period 6 and 5904 times period 12.
LINKS
Wouter Meeussen, Periodic
Eric Weisstein's World of Mathematics, Periodic Matrices
CROSSREFS
Cf. A072148.
Sequence in context: A141535 A324313 A377578 * A293126 A080447 A127059
KEYWORD
hard,nonn
AUTHOR
Wouter Meeussen, Nov 15 2005
STATUS
approved