New Type B Colorable S(2, 4, V) Designs

An S(2, 4, v) design has a type B chi-coloring if it is possible to assign one of chi colors to each point such that each block contains three points of one color and one point of a different color, and all chi colors are used. In this article we describe the constructions of type B chi-colorable S(2, 4, v)s for (v, chi) = (61, 3), (100, 2) and (109, 3), and we give a new general construction. (c) 2007 Wiley Periodicals, Inc.