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A330967
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a(n) is the determinant of the matrix with elements gcd(i,j) for 2 <= i,j <= n.
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0
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2, 5, 10, 44, 104, 656, 2624, 15744, 67584, 694272, 2777088, 34062336, 213221376, 1758855168, 14070841344, 228530847744, 1371185086464, 25007480635392, 200059845083136, 2447683608379392, 25040421692375040, 556525133318062080, 4452201066544496640, 89044021330889932800
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OFFSET
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2,1
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COMMENTS
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These determinants are always nonzero, as shown by Beslin and Ligh.
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LINKS
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MATHEMATICA
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Table[Det[Table[GCD[i, j], {i, 2, n}, {j, 2, n}]], {n, 2, 25}]
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PROG
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(PARI) a(n)={matdet(matrix(n-1, n-1, i, j, gcd(i+1, j+1)))} \\ Andrew Howroyd, Jan 07 2020
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CROSSREFS
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A001088 gives the determinants for gcd(i,j), 1 <= i,j <= n.
A067549 gives the determinants for gcd(i-th prime, j-th prime), 1 <= i,j <= n.
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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