A358809 - OEIS

%I #14 Dec 07 2022 14:58:47

%S 1,0,4,186,21823,4569098,1713573909

%N a(n) is the maximal permanent of an n X n symmetric matrix using all the integers from 0 to n*(n + 1)/2 - 1.

%e a(2) = 4:

%e     [0, 2;

%e      2, 1]

%e a(3) = 186:

%e     [0, 4, 5;

%e      4, 2, 3;

%e      5, 3, 1]

%Y Cf. A000217, A351153, A351611.

%Y Cf. A358806 (minimal determinant), A358807 (maximal determinant), A358808 (minimal).

%K nonn,hard,more

%O 0,3

%A _Stefano Spezia_, Dec 02 2022

%E a(5)-a(6) from _Hugo Pfoertner_, Dec 07 2022