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A348891
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Minimal absolute value of determinant of a nonsingular n X n symmetric Toeplitz matrix using the first n prime numbers.
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9
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1, 2, 5, 12, 11, 22, 84, 1368, 73, 589, 15057, 2520, 28209
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OFFSET
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0,2
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LINKS
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EXAMPLE
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a(3) = 12:
2 3 5
3 2 3
5 3 2
a(4) = 11:
2 5 3 7
5 2 5 3
3 5 2 5
7 3 5 2
a(5) = 22:
2 3 5 7 11
3 2 3 5 7
5 3 2 3 5
7 5 3 2 3
11 7 5 3 2
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PROG
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(Python)
from itertools import permutations
from sympy import Matrix, prime
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(prime(i) for i in range(1, n+1))) if d > 0) # Chai Wah Wu, Jan 28 2022
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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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EXTENSIONS
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STATUS
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approved
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