a-a a-b a-t aaa aab aae aao aap aat ab- aba abb abe abo abp abt aea aeb aee aeo aep aet aoa aob aoe aoo aop aot ap- apa apb ape apo app apt at- ata atb ate ato atp att b-p baa bab bae bao bap bat bba bbb bbe bbo bbp bbt be- bea beb bee beo bep bet boa bob boe boo bop bot bpa bpb bpe bpo bpp bpt bta btb bte bto btp btt eaa eab eae eao eap eat eba ebb ebe ebo ebp ebt eea eeb eee eeo eep eet eo- eoa eob eoe eoo eop eot ep- epa epb epe epo epp ept eta etb ete eto etp ett oaa oab oae oao oap oat ob- oba obb obe obo obp obt oea oeb oee oeo oep oet oo- ooa oob ooo oop oot op- opa opb ope opo opp opt ot- ota otb ote oto otp ott p-p paa pab pae pao pap pat pba pbb pbe pbo pbp pbt pea peb pee peo pep pet poa pob poe poo pop pot ppa ppb ppe ppo ppp ppt pt- pta ptb pte pto ptp ptt taa tab tae tao tap tat tba tbb tbe tbo tbp tbt te- tea teb tee teo tep tet to- toa tob toe too top tot tpa tpb tpe tpo tpp tpt tta ttb tte tto ttp ttt