Further Remarks on Long Monochromatic Cycles in Edge-Colored Complete Graphs

Shinya Fujita1, Linda Lesniakt Agnes Toth2
1Department of Integrated Design Engineering, Maebashi Institute of Technology, Maebashi 371-0816 Japan
2Department of Mathematics and Computer Science, Drew University, Madison, NJ 07940 USA & Department of Mathematics, Western Michigan University, Kalamazoo, MI 49008 USA

Abstract

In [Discrete Math., 311 (2011), 688-689], Fujita defined \( f(r,n) \) to be the maximum integer \( k \) such that every \( r \)-edge-coloring of \( K_n \) contains a monochromatic cycle of length at least \( k \). In this paper, we investigate the values of \( f(r,n) \) when \( n \) is linear in \( r \). We determine the value of \( f(r, 2r+2) \) for all \( r \geq 1 \) and show that \( f(r, sr+c) = s+1 \) if \( r \) is sufficiently large compared with positive integers \( s \) and \( c \).