a-a a-b aaa aab aae aak aam aao aav ab- aba abb abe abk abm abo abv aea aeb aee aek aem aeo aev aka akb ake akk akm ako akv ama amb ame amk amm amo amv aoa aob aoe aok aom aoo aov av- ava avb ave avk avm avo baa bab bae bak bam bao bav bba bbb bbe bbk bbm bbo be- bea beb bee bek bem beo bev bka bkb bke bkk bkm bko bkv bma bmb bme bmk bmm bmo bmv boa bob boe bok bom boo bov bva bvb bve bvk bvm bvo bvv eaa eab eae eak eam eao eav eba ebb ebe ebk ebm ebo ebv eea eeb eee eek eem eeo eev eka ekb eke eko ekv em- ema emb eme emk emm emo emv eo- eoa eob eoe eok eom eoo eva evb eve evm evo evv ka- kaa kab kae kak kam kao kav kba kbb kbe kbk kbm kbo ke- kea keb kee kek kem keo kev kkb kke kkk kkm kkv kma kmb kme kmk kmm kmo koa kob koe kok kom koo kva kvb kvk kvm kvo kvv m-o m-v maa mab mae mak mam mao mav mba mbb mbe mbk mbm mbo mbv mea meb mee mek mem meo mev mka mkb mke mkk mkm mko mkv mma mmb mme mmk mmm mmo mmv moa mob moe mok mom moo mov mva mvb mve mvm mvo mvv oaa oab oae oak oam oao oav ob- oba obb obe obk obm obo obv oea oeb oee oem oeo oka okb oke okk oko om- oma omb ome omm omo omv oo- ooa oob ook oom ooo oov ov- ova ovb ove ovo ovv v-a v-e vaa vab vae vak vam vao vav vba vbk vbm vbo vbv vea veb vee vek vem veo vka vkb vkm vm- vma vmm vmo voa vob voe vok vom voo vov vva vvb vvm vvo vvv