a-a aaa aak aan aao aar aka akk akn ako akr an- ana ank ann ano anr aoa aok aon aoo aor ar- ara ark arn aro arr ka- kaa kak kan kao kar kkk kkn kkr kn- kna knk knn kno knr koa kok kon koo kor kra krk krn kro krr naa nak nan nao nar nka nkk nkn nko nkr nna nnk nnn nno no- noa nok non noo nor nra nrk nrn nro nrr oaa oak oan oao oar oka okk oko okr on- ona onk onn ono onr oo- ooa ook oon ooo oor or- ora ork orn oro orr ra- raa rak ran rao rar rkk rko rna rnn rno rnr roa rok ron roo ror rra rrk rrn rrr