1,2

A lower bound on A121231(n), the maximal number of 1's in any (0,1)-matrix M such that M^2 is also a (0,1)-matrix.

For example, for m^2 x m^2 matrices one can obtain a(m^2) = m^3 using m^2 m x m matrices with one row of m of 1's and (m-1) rows of m of 0's.

Table of n, a(n) for n=1..25.

Sequence in context: A294127 A166955 A286808 * A039770 A236019 A247426

Adjacent sequences: A121291 A121292 A121293 * A121295 A121296 A121297

nonn

Dan Dima, Aug 24 2006

Edited by R. J. Mathar, Oct 01 2008

approved