This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A356865 #12 Oct 11 2022 00:55:10 %S A356865 1,1,3,8,12,3,13,19,5,5,1,3,1 %N A356865 Minimal absolute value of determinant of a nonsingular n X n symmetric Toeplitz matrix using the integers 1 to n. %H A356865 Lucas A. Brown, <a href="https://github.com/lucasaugustus/oeis/blob/main/A350953%2B4%2BA356865.py">A350953+4+A356865.py</a> %H A356865 Wikipedia, <a href="http://en.wikipedia.org/wiki/Toeplitz_matrix">Toeplitz Matrix</a> %e A356865 a(3) = 8: %e A356865 1 2 3 %e A356865 2 1 2 %e A356865 3 2 1 %e A356865 a(4) = 12: %e A356865 2 1 3 4 %e A356865 1 2 1 3 %e A356865 3 1 2 1 %e A356865 4 3 1 2 %e A356865 a(5) = 3: %e A356865 1 5 2 3 4 %e A356865 5 1 5 2 3 %e A356865 2 5 1 5 2 %e A356865 3 2 5 1 5 %e A356865 4 3 2 5 1 %o A356865 (Python) %o A356865 from itertools import permutations %o A356865 from sympy import Matrix %o A356865 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) %Y A356865 Cf. A350953 (minimal signed), A350954 (maximal signed), A348891 (prime entries). %K A356865 nonn,hard,more %O A356865 0,3 %A A356865 _Lucas A. Brown_, Sep 01 2022