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A351021 Minimal permanent of an n X n symmetric Toeplitz matrix using the first n prime numbers.

%I A351021 #19 Oct 13 2022 06:48:54
%S A351021 1,2,13,166,4009,169469,10949857,1078348288,138679521597,
%T A351021 24402542896843,5348124003487173
%N A351021 Minimal permanent of an n X n symmetric Toeplitz matrix using the first n prime numbers.
%H A351021 Lucas A. Brown, <a href="https://github.com/lucasaugustus/oeis/blob/main/A351021%2B2.sage">A351021+2.sage</a>
%H A351021 Wikipedia, <a href="http://en.wikipedia.org/wiki/Toeplitz_matrix">Toeplitz Matrix</a>
%e A351021 a(3) = 166:
%e A351021     3    2    5
%e A351021     2    3    2
%e A351021     5    2    3
%e A351021 a(4) = 4009:
%e A351021     3    2    5    7
%e A351021     2    3    2    5
%e A351021     5    2    3    2
%e A351021     7    5    2    3
%e A351021 a(5) = 169469:
%e A351021     5    2    3    7   11
%e A351021     2    5    2    3    7
%e A351021     3    2    5    2    3
%e A351021     7    3    2    5    2
%e A351021    11    7    3    2    5
%o A351021 (Python)
%o A351021 from itertools import permutations
%o A351021 from sympy import Matrix, prime
%o A351021 def A351021(n): return 1 if n == 0 else min(Matrix([p[i:0:-1]+p[0:n-i] for i in range(n)]).per() for p in permutations(prime(i) for i in range(1,n+1))) # _Chai Wah Wu_, Jan 31 2022
%Y A351021 Cf. A348891, A350939, A350955, A351022 (maximal).
%K A351021 nonn,hard,more
%O A351021 0,2
%A A351021 _Stefano Spezia_, Jan 29 2022
%E A351021 a(9) and a(10) from _Lucas A. Brown_, Sep 04 2022