a-a a-b aaa aab aan aao aap aay ab- aba abb abn abo abp aby an- ana anb ann ano anp any aoa aob aon aoo aop ap- apa apb apn apo app apy ay- aya ayn ayo ayp b-p baa bab ban bao bap bay bba bbb bbn bbo bbp bby bna bnb bnn bno bnp boa bob bon boo bop boy bpa bpb bpn bpo bpp bpy by- bya byn byo byp naa nab nan nao nap nay nba nbb nbn nbo nbp nna nnb nnn nno nnp no- noa nob non noo nop noy npa npb npn npo npp nya nyn nyo nyp nyy oaa oab oan oao oap ob- oba obb obn obo obp oby on- ona onb onn ono onp ony oo- ooa oob oon ooo oop op- opa opb opn opo opp opy oya oyo p-p paa pab pan pao pap pay pba pbb pbn pbo pbp pby pn- pna pnb pnn pno pnp pny poa pob pon poo pop poy ppa ppb ppn ppo ppp py- pya pyb pyn pyo yaa yab yan yao yap yay ybp yby yna ynn ynp yny yob yon yoo yop yoy ypa ypo yyb yyy