New complete 2-arcs in the uniform projective Hjelmslev planes over chain rings of order 25

Michael Kiermaier, Matthias Koch

In this paper a 2-arc of size 21 in the projective Hjelmslev plane PHG(2,\Z_25) and a 2-arc of size 22 in PHG(2,\F_5[X]/(X^2)) are given. Both arcs are bigger than the 2-arcs previ…