cp's OEIS Frontend

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.

A348891 Minimal absolute value of determinant of a nonsingular n X n symmetric Toeplitz matrix using the first n prime numbers.

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