4,1
a(n) is the least k such that every n X (n+1) {0,1}-matrix with k ones contains an all ones 4 X 4 submatrix. - Sean A. Irvine, May 18 2017
R. K. Guy, A many-facetted problem of Zarankiewicz, Lect. Notes Math. 110 (1969), 129-148.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
Table of n, a(n) for n=4..8.
Sequence in context: A160036 A032701 A226726 * A259054 A029510 A029537
Adjacent sequences: A006623 A006624 A006625 * A006627 A006628 A006629
nonn,more
N. J. A. Sloane.
approved
