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%I #11 Feb 11 2024 11:28:44
%S 1,1,1,6,23,119,718,5038,40320,362879
%N a(n) is the number of distinct values of the permanent of an n X n symmetric Toeplitz matrix using the integers 0 to n-1.
%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Toeplitz_matrix">Toeplitz Matrix</a>.
%F a(n) <= A000142(n).
%t a[n_] := CountDistinct[Table[Permanent[ToeplitzMatrix[Part[Permutations[Join[{0}, Range[n - 1]]], i]]], {i, n !}]]; Join[{1}, Array[a,9]]
%o (Python)
%o from itertools import permutations
%o from sympy import Matrix
%o def A369835(n): return len({Matrix([p[i:0:-1]+p[:n-i] for i in range(n)]).per() for p in permutations(range(n))}) # _Chai Wah Wu_, Feb 11 2024
%Y Cf. A000142, A358326, A358327.
%Y Cf. A369830, A369831, A369832, A369833, A369834.
%K nonn,hard,more
%O 0,4
%A _Stefano Spezia_, Feb 03 2024