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A358808
a(n) is the minimal permanent of an n X n symmetric matrix using all the integers from 0 to n*(n + 1)/2 - 1.
4
1, 0, 1, 33, 2425, 357046, 92052610
OFFSET
0,4
EXAMPLE
a(2) = 1:
[0, 1;
1, 2]
a(3) = 33:
[0, 1, 2;
1, 3, 4;
2, 4, 5]
a(4) = 2425:
[0, 2, 3, 1;
2, 8, 7, 4;
3, 7, 9, 6;
1, 4, 6, 5]
CROSSREFS
Cf. A358806 (minimal determinant), A358807 (maximal determinant), A358809 (maximal).
Sequence in context: A372903 A118641 A263908 * A111922 A136541 A263105
KEYWORD
nonn,hard,more
AUTHOR
Stefano Spezia, Dec 02 2022
EXTENSIONS
a(4) corrected and a(5)-a(6) from Hugo Pfoertner, Dec 07 2022
STATUS
approved