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A351148
a(n) is the maximal determinant of a symmetric n X n matrix using the integers 1 to n*(n+1)/2.
3
1, 5, 112, 7113, 745285, 90536348
OFFSET
1,2
EXAMPLE
a(2) = 5:
[2, 1;
1, 3]
.
a(3) = 112:
[1, 5, 4;
5, 3, 6;
4, 6, 2]
.
a(4) = 7113:
[ 3, 10, 4, 8;
10, 5, 1, 6;
4, 1, 7, 9;
8, 6, 9, 2]
.
a(5) = 745285:
[10, 12, 1, 4, 13;
12, 6, 5, 15, 3;
1, 5, 9, 11, 14;
4, 15, 11, 7, 2;
13, 3, 14, 2, 8]
.
a(6) = 90536348:
[18, 1, 7, 14, 6, 15;
1, 13, 5, 17, 8, 20;
7, 5, 12, 2, 21, 16;
14, 17, 2, 11, 19, 3;
6, 8, 21, 19, 9, 4;
15, 20, 16, 3, 4, 10]
CROSSREFS
KEYWORD
nonn,hard,more
AUTHOR
Hugo Pfoertner at the suggestion of Markus Sigg, Feb 15 2022
STATUS
approved