a-a a-b a-i aaa aab aai aao aar aas aav ab- aba abb abi abo abr abs abv ai- aia aib aii aio air ais aiv aoa aob aoi aoo aor aos aov ar- ara arb ari aro arr ars arv as- asa asb asi aso asr ass asv av- ava avb avi avo avr avs baa bab bai bao bar bas bav bba bbb bbi bbo bbr bbs bi- bia bib bii bio bir bis biv boa bob boi boo bor bos bov bra brb bri bro brr brs brv bsa bsb bsi bso bsr bss bsv bva bvb bvi bvo bvr bvs bvv i-v ia- iaa iab iai iao iar ias iav iba ibb ibi ibo ibr ibs ibv iia iib iii iio iir iis io- ioa iob ioi ioo ior ios iov ir- ira irb iri iro irr irs irv is- isa isb isi iso isr iss isv iva ivb ivi ivo ivr ivs ivv o-i oaa oab oai oao oar oas oav ob- oba obb obi obo obr obs obv oia oib oii oio oir ois oiv oo- ooa oob ooi ooo oor oos oov or- ora orb ori oro orr ors orv os- osa osb osi oso osr oss osv ov- ova ovb ovi ovo ovs ovv ra- raa rab rai rao rar ras rav rba rbb rbi rbo rbr rbs ria rib rii rio rir ris riv roa rob roi roo ror ros rov rra rrb rri rrr rrs rsa rsb rsi rso rsr rss rsv rva rvb rvi rvo rvr rvs rvv saa sab sai sao sar sas sav sba sbb sbi sbo sbr sbs sbv sia sib sii sio sir sis siv soa sob soi soo sor sos sov sr- sra srb sri sro srr srs srv ss- ssa ssb ssi sso ssr sss ssv sva svb svi svo svr svs svv v-a vaa vab vai vao var vas vav vba vbi vbo vbr vbs vbv vi- via vib vii vio vir vis viv voa vob voi voo vor vos vov vra vrb vri vrr vrs vsa vsb vsi vso vsr vss vsv vva vvb vvi vvo vvr vvs vvv