a-a a-b a-i a-t aaa aab aai aao aar aas aat aav ab- aba abb abi abo abr abs abt abv ai- aia aib aii aio air ais ait aiv aoa aob aoi aoo aor aos aot aov ar- ara arb ari aro arr ars art arv as- asa asb asi aso asr ass ast asv at- ata atb ati ato atr ats att atv av- ava avb avi avo avr avs avt baa bab bai bao bar bas bat bav bba bbb bbi bbo bbr bbs bbt bi- bia bib bii bio bir bis bit biv boa bob boi boo bor bos bot bov bra brb bri bro brr brs brt brv bsa bsb bsi bso bsr bss bst bsv bta btb bti bto btr bts btt btv bva bvb bvi bvo bvr bvs bvt bvv i-v ia- iaa iab iai iao iar ias iat iav iba ibb ibi ibo ibr ibs ibt ibv iia iib iii iio iir iis iit io- ioa iob ioi ioo ior ios iot iov ir- ira irb iri iro irr irs irt irv is- isa isb isi iso isr iss ist isv ita itb iti ito its itt itv iva ivb ivi ivo ivr ivs ivt ivv o-i oaa oab oai oao oar oas oat oav ob- oba obb obi obo obr obs obt obv oia oib oii oio oir ois oit oiv oo- ooa oob ooi ooo oor oos oot oov or- ora orb ori oro orr ors ort orv os- osa osb osi oso osr oss ost osv ot- ota otb oti oto otr ots ott otv ov- ova ovb ovi ovo ovs ovv ra- raa rab rai rao rar ras rat rav rba rbb rbi rbo rbr rbs rbt ria rib rii rio rir ris rit riv roa rob roi roo ror ros rot rov rra rrb rri rrr rrs rrt rsa rsb rsi rso rsr rss rst rsv rta rtb rti rto rtr rts rtt rtv rva rvb rvi rvo rvr rvs rvt rvv saa sab sai sao sar sas sat sav sba sbb sbi sbo sbr sbs sbt sbv sia sib sii sio sir sis sit siv soa sob soi soo sor sos sot sov sr- sra srb sri sro srr srs srt srv ss- ssa ssb ssi sso ssr sss sst ssv sta stb sti sto str sts stt stv sva svb svi svo svr svs svt svv taa tab tai tao tar tas tat tav tba tbb tbi tbo tbr tbs tbt tbv tia tib tii tio tir tis tit tiv to- toa tob toi too tor tos tot tov tra trb tri tro trr trs trt trv tsa tsb tsi tso tsr tss tst tsv tta ttb tti tto ttr tts ttt ttv tva tvb tvi tvo tvr tvs tvt v-a vaa vab vai vao var vas vat vav vba vbi vbo vbr vbs vbv vi- via vib vii vio vir vis vit viv voa vob voi voo vor vos vot vov vra vrb vri vrr vrs vrt vsa vsb vsi vso vsr vss vst vsv vta vtb vti vto vtr vts vtt vtv vva vvb vvi vvo vvr vvs vvt vvv