a-a a-b a-i aaa aab aai aak aap ab- aba abb abi abk abp ai- aia aib aii aik aip aka akb aki akk akp ap- apa apb api apk app b-p baa bab bai bak bap bba bbb bbi bbk bbp bi- bia bib bii bik bip bka bkb bkk bkp bpa bpb bpi bpp ia- iaa iab iai iap iba ibb ibi ibk ibp iia iib iii iip ika ikb iki ikk ipa ipb ipi ipp ka- kaa kab kai kak kap kba kbb kbi kbk kbp kia kib kii kik kip kkb kki kkk kkp kpa kpi kpk kpp p-p paa pab pai pak pap pba pbb pbi pbk pbp pia pib pii pik pip pka pkb pki pkp ppa ppb ppi ppk ppp