-ic a-a a-b a-c a-i a-t aaa aab aac aaf aai aao aar aas aat ab- aba abb abc abf abi abo abr abs abt ac- aca acb acc acf aci aco acr acs act af- afa afb afc aff afi afo afr afs aft ai- aia aib aic aif aii aio air ais ait aoa aob aoc aof aoi aoo aor aos aot ar- ara arb arc arf ari aro arr ars art as- asa asb asc asf asi aso asr ass ast at- ata atb atc atf ati ato atr ats att baa bab bac baf bai bao bar bas bat bba bbb bbc bbf bbi bbo bbr bbs bbt bca bcb bcc bcf bci bco bcr bcs bct bfa bfb bfc bff bfi bfo bfr bfs bft bi- bia bib bic bif bii bio bir bis bit boa bob boc bof boi boo bor bos bot bra brb brf bri bro brr brs brt bsa bsb bsc bsf bsi bso bsr bss bst bta btb btc btf bti bto btr bts btt c-- caa cab cac caf cai cao car cas cat cba cbb cbc cbf cbi cbo cbr cbs cbt cca ccb ccc ccf cci cco ccr ccs cct cfa cfb cfc cff cfi cfo cfr cfs cft ci- cia cib cic cif cii cio cir cis cit co- coa cob coc cof coi coo cor cos cot cra crb crc crf cri cro crr crs crt csa csb csc csf csi cso csr css cst cta ctb ctc ctf cti cto ctr cts ctt faa fab fac faf fai fao far fas fat fba fbb fbc fbf fbi fbo fbr fbs fbt fca fcb fcc fcf fci fco fcr fcs fct ffa ffc fff ffi ffo ffr ffs fft fia fib fic fif fii fir fis fit foa fob foc fof foi foo for fos fot fra frb frc frf fri fro frr frs frt fsa fsb fsc fsf fsi fso fsr fss fst fta ftb ftc ftf fti fto ftr fts ftt i-f ia- iaa iab iac iaf iai iao iar ias iat iba ibb ibc ibf ibi ibo ibr ibs ibt ica icb icc icf ici ico icr ics ict ifa ifb ifc iff ifi ifo ifr ifs ift iia iib iic iif iii iio iir iis iit io- ioa iob ioc iof ioi ioo ior ios iot ir- ira irb irc irf iri iro irr irs irt is- isa isb isc isf isi iso isr iss ist ita itb itc itf iti ito its itt o-i oaa oab oac oaf oai oao oar oas oat ob- oba obb obc obf obi obo obr obs obt oc- oca ocb occ ocf oci oco ocr ocs oct of- ofa ofb ofc off ofi ofo ofr ofs oft oia oib oic oif oii oio oir ois oit oo- ooa oob ooc oof ooi ooo oor oos oot or- ora orb orc orf ori oro orr ors ort os- osa osb osc osf osi oso osr oss ost ot- ota otb otc otf oti oto otr ots ott ra- raa rab rac raf rai rao rar ras rat rba rbb rbc rbf rbi rbo rbr rbs rbt rca rcb rcc rcf rci rco rcr rcs rct rfa rfb rfc rff rfi rfo rfr rfs rft ria rib ric rif rii rio rir ris rit roa rob roc rof roi roo ror ros rot rra rrb rrc rrf rri rrr rrs rrt rsa rsb rsc rsf rsi rso rsr rss rst rta rtb rtc rtf rti rto rtr rts rtt saa sab sac saf sai sao sar sas sat sba sbb sbc sbf sbi sbo sbr sbs sbt sca scb scc scf sci sco scr scs sct sfa sfb sfc sff sfi sfo sfr sfs sft sia sib sic sif sii sio sir sis sit soa sob soc sof soi soo sor sos sot sr- sra srb src srf sri sro srr srs srt ss- ssa ssb ssc ssf ssi sso ssr sss sst sta stb stc stf sti sto str sts stt taa tab tac taf tai tao tar tas tat tba tbb tbc tbf tbi tbo tbr tbs tbt tca tcb tcc tcf tci tco tcr tcs tct tfa tfb tfc tff tfi tfo tfr tfs tft tia tib tic tif tii tio tir tis tit to- toa tob toc tof toi too tor tos tot tra trb trc trf tri tro trr trs trt tsa tsb tsc tsf tsi tso tsr tss tst tta ttb ttc ttf tti tto ttr tts ttt