

A331439


Number of singular n X n matrices whose rows are distinct (0,1) vectors arranged in increasing order.


0




OFFSET

1,2


COMMENTS

It appears that the determinant is computed over the rationals, not over GF(2).


REFERENCES

M. B. Wells, Elements of Combinatorial Computing, Pergamon, Oxford, 1971.


LINKS

Table of n, a(n) for n=1..7.
J. S. Huang and B. L. Raktoe, A note on the proportion of singular (0, 1)matrices in a class associated with fractional 2n factorial designs, Journal of Combinatorial Theory, Series A 22.2 (1977): 231234.


EXAMPLE

The three 2 X 2 matrices are [00/01], [00/10], [00/11].


CROSSREFS

Sequence in context: A326086 A194500 A012505 * A085521 A009066 A279832
Adjacent sequences: A331436 A331437 A331438 * A331440 A331441 A331442


KEYWORD

nonn,more


AUTHOR

N. J. A. Sloane, Jan 21 2020


STATUS

approved



