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A356865
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Minimal absolute value of determinant of a nonsingular n X n symmetric Toeplitz matrix using the integers 1 to n.
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8
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1, 1, 3, 8, 12, 3, 13, 19, 5, 5, 1, 3, 1
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OFFSET
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0,3
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LINKS
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EXAMPLE
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a(3) = 8:
1 2 3
2 1 2
3 2 1
a(4) = 12:
2 1 3 4
1 2 1 3
3 1 2 1
4 3 1 2
a(5) = 3:
1 5 2 3 4
5 1 5 2 3
2 5 1 5 2
3 2 5 1 5
4 3 2 5 1
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PROG
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(Python)
from itertools import permutations
from sympy import Matrix
def A348891(n): return min(d for d in (abs(Matrix([p[i:0:-1]+p[0:n-i] for i in range(n)]).det()) for p in permutations(range(1, n+1))) if d > 0)
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CROSSREFS
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KEYWORD
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nonn,hard,more
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AUTHOR
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STATUS
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approved
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