

A006621


Zarankiewicz's problem k_3(n,n+1).
(Formerly M4776)


1




OFFSET

3,1


COMMENTS

a(n) is the least k such that every n X (n+1) {0,1}matrix with k ones contains an all ones 3 X 3 submatrix.  Sean A. Irvine, May 18 2017


REFERENCES

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).


LINKS

Table of n, a(n) for n=3..12.
R. K. Guy, A manyfacetted problem of Zarankiewicz, Lect. Notes Math. 110 (1969), 129148.


CROSSREFS

Cf. A001198 (k_3(n)), A006620 (k_2(n,n+1)), A006626 (k_4(n,n+1)).
Sequence in context: A275682 A265402 A145481 * A337359 A275596 A158913
Adjacent sequences: A006618 A006619 A006620 * A006622 A006623 A006624


KEYWORD

nonn,more


AUTHOR

N. J. A. Sloane


EXTENSIONS

a(10)a(12) from Andrew Howroyd, Dec 26 2021


STATUS

approved



