a-a a-b aaa aab aah aao aap ab- aba abb abh abo abp aha ahb ahh aho ahp aoa aob aoh aoo aop ap- apa apb aph apo app b-p baa bab bah bao bap bba bbb bbh bbo bbp bha bhb bhh bho bhp boa bob boh boo bop bpa bpb bph bpo bpp haa hab hah hao hap hba hbb hbh hbo hbp hha hhb hhh hho hhp hoa hob hoh hoo hop hpa hpb hph hpo hpp oaa oab oah oao oap ob- oba obb obh obo obp oha ohh oho ohp oo- ooa oob ooh ooo oop op- opa opb oph opo opp p-p paa pab pah pao pap pba pbb pbo pbp pha phb pho php poa pob poh poo pop ppa ppb pph ppo ppp