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A171808
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Number of 5 X 5 permutation matrices such that the n-th matrix power is the identity matrix and the determinant is +1.
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4
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OFFSET
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1,2
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COMMENTS
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Sum of this sequence is equal to the number of permutation matrices with determinant +1 = 5!/2 = 60. For number matrices with determinant = -1 see A171809.
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LINKS
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EXAMPLE
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a(1)=1 because there is only one matrix whose first power is the identity matrix (this is the identity matrix itself).
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CROSSREFS
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KEYWORD
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fini,nonn,full
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AUTHOR
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STATUS
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approved
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