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%I #25 Oct 12 2022 08:24:28
%S 1,2,5,12,11,22,84,1368,73,589,15057,2520,28209
%N Minimal absolute value of determinant of a nonsingular n X n symmetric Toeplitz matrix using the first n prime numbers.
%H Lucas A. Brown, <a href="https://github.com/lucasaugustus/oeis/blob/main/A348891%2BA350955%2B6.py">A348891+A350955+6.py</a>
%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Toeplitz_matrix">Toeplitz Matrix</a>
%e a(3) = 12:
%e 2 3 5
%e 3 2 3
%e 5 3 2
%e a(4) = 11:
%e 2 5 3 7
%e 5 2 5 3
%e 3 5 2 5
%e 7 3 5 2
%e a(5) = 22:
%e 2 3 5 7 11
%e 3 2 3 5 7
%e 5 3 2 3 5
%e 7 5 3 2 3
%e 11 7 5 3 2
%o (Python)
%o from itertools import permutations
%o from sympy import Matrix, prime
%o 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
%Y Cf. A350932, A350955.
%K nonn,hard,more
%O 0,2
%A _N. J. A. Sloane_ and _Stefano Spezia_, Jan 28 2022
%E a(9) from _Alois P. Heinz_, Jan 28 2022
%E a(10)-a(12) from _Lucas A. Brown_, Aug 31 2022
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