941n2u a51n b51n2 c51n2u d51n
yv2n zv2n2 0v2n2u 1v2n 2v2n2
nm3n2 om3n2u pm3n qm3n2 rm3n2u
cd4n2u dd4n ed4n2 fd4n2u gd4n
134n 234n2 334n2u 434n 534n2