a-a a-b a-i aaa aab aai aam aao ab- aba abb abi abm abo ai- aia aib aii aim aio ama amb ami amm amo aoa aob aoi aom aoo baa bab bai bam bao bba bbb bbi bbm bbo bi- bia bib bii bim bio bma bmb bmi bmm bmo boa bob boi bom boo ia- iaa iab iai iam iao iba ibb ibi ibm ibo iia iib iii iim iio im- ima imb imi imm imo io- ioa iob ioi iom ioo m-o maa mab mai mam mao mba mbb mbi mbm mbo mi- mia mib mii mim mio mma mmb mmi mmm mmo moa mob moi mom moo o-i oaa oab oai oam oao ob- oba obb obi obm obo oia oib oii oim oio om- oma omb omi omm omo oo- ooa oob ooi oom ooo