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A260340
Triangle read by rows: T(n,k) = number of sets of linear n-ads in k variables.
6
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 6, 1, 1, 1, 1, 22, 22, 1, 1, 1, 1, 130, 550, 130, 1, 1, 1, 1, 822, 16700, 16700, 822, 1, 1, 1, 1, 6202, 703297, 3330915, 703297, 6202, 1, 1, 1, 1, 52552, 38135272, 957659906, 957659906, 38135272, 52552, 1, 1
OFFSET
0,13
COMMENTS
T(n,k) is the number of nonequivalent n X n binary matrices with k ones in every row and column up to permutation of rows. - Andrew Howroyd, Apr 18 2020
LINKS
FORMULA
T(n,k) = T(n,n-k). - Andrew Howroyd, Apr 18 2020
EXAMPLE
Triangle begins:
1;
1, 1;
1, 1, 1;
1, 1, 1, 1;
1, 1, 6, 1, 1;
1, 1, 22, 22, 1, 1;
1, 1, 130, 550, 130, 1, 1;
1, 1, 822, 16700, 16700, 822, 1, 1;
1, 1, 6202, 703297, 3330915, 703297, 6202, 1, 1;
...
CROSSREFS
Columns k=0..4 are A000012, A000012, A002137, A333899, A333900.
Row sums are A333891.
Sequence in context: A339747 A293901 A324891 * A040037 A344877 A356156
KEYWORD
nonn,tabl
AUTHOR
N. J. A. Sloane, Jul 30 2015
EXTENSIONS
Extended to include k=0 and more terms added by Andrew Howroyd, Apr 18 2020
STATUS
approved