-ic a-a a-b a-c a-i aaa aab aac aaf aai aan aao aar aas ab- aba abb abc abf abi abn abo abr abs ac- aca acb acc acf aci acn aco acr acs af- afa afb afc aff afi afn afo afr afs ai- aia aib aic aif aii ain aio air ais an- ana anb anc anf ani ann ano anr ans aoa aob aoc aof aoi aon aoo aor aos ar- ara arb arc arf ari arn aro arr ars as- asa asb asc asf asi asn aso asr ass baa bab bac baf bai ban bao bar bas bba bbb bbc bbf bbi bbn bbo bbr bbs bca bcb bcc bcf bci bcn bco bcr bcs bfa bfb bfc bff bfi bfn bfo bfr bfs bi- bia bib bic bif bii bin bio bir bis bna bnb bnc bnf bni bnn bno bnr bns boa bob boc bof boi bon boo bor bos bra brb brf bri brn bro brr brs bsa bsb bsc bsf bsi bsn bso bsr bss c-- caa cab cac caf cai can cao car cas cba cbb cbc cbf cbi cbn cbo cbr cbs cca ccb ccc ccf cci ccn cco ccr ccs cfa cfb cfc cff cfi cfn cfo cfr cfs ci- cia cib cic cif cii cin cio cir cis cn- cna cnb cnc cnf cni cnn cno cnr cns co- coa cob coc cof coi con coo cor cos cra crb crc crf cri crn cro crr crs csa csb csc csf csi csn cso csr css faa fab fac faf fai fan fao far fas fba fbb fbc fbf fbi fbn fbo fbr fbs fca fcb fcc fcf fci fcn fco fcr fcs ffa ffc fff ffi ffn ffo ffr ffs fia fib fic fif fii fin fir fis fna fnb fnc fnf fni fnn fnr fns foa fob foc fof foi fon foo for fos fra frb frc frf fri frn fro frr frs fsa fsb fsc fsf fsi fsn fso fsr fss i-f ia- iaa iab iac iaf iai ian iao iar ias iba ibb ibc ibf ibi ibn ibo ibr ibs ica icb icc icf ici icn ico icr ics ifa ifb ifc iff ifi ifn ifo ifr ifs iia iib iic iif iii iin iio iir iis in- ina inb inc inf ini inn ino inr ins io- ioa iob ioc iof ioi ion ioo ior ios ir- ira irb irc irf iri irn iro irr irs is- isa isb isc isf isi isn iso isr iss n-i naa nab nac naf nai nan nao nar nas nba nbb nbc nbf nbi nbn nbo nbr nbs nca ncb ncc ncf nci ncn nco ncr ncs nfa nfb nfc nff nfi nfn nfo nfr nfs nia nib nic nif nii nin nio nir nis nna nnb nnc nnf nni nnn nno nns no- noa nob noc nof noi non noo nor nos nra nrb nrc nrf nri nrn nro nrr nrs nsa nsb nsc nsf nsi nsn nso nsr nss o-i oaa oab oac oaf oai oan oao oar oas ob- oba obb obc obf obi obn obo obr obs oc- oca ocb occ ocf oci ocn oco ocr ocs of- ofa ofb ofc off ofi ofn ofo ofr ofs oia oib oic oif oii oin oio oir ois on- ona onb onc onf oni onn ono onr ons oo- ooa oob ooc oof ooi oon ooo oor oos or- ora orb orc orf ori orn oro orr ors os- osa osb osc osf osi osn oso osr oss ra- raa rab rac raf rai ran rao rar ras rba rbb rbc rbf rbi rbn rbo rbr rbs rca rcb rcc rcf rci rcn rco rcr rcs rfa rfb rfc rff rfi rfn rfo rfr rfs ria rib ric rif rii rin rio rir ris rna rnb rnc rni rnn rno rnr rns roa rob roc rof roi ron roo ror ros rra rrb rrc rrf rri rrn rrr rrs rsa rsb rsc rsf rsi rsn rso rsr rss saa sab sac saf sai san sao sar sas sba sbb sbc sbf sbi sbn sbo sbr sbs sca scb scc scf sci scn sco scr scs sfa sfb sfc sff sfi sfn sfo sfr sfs sia sib sic sif sii sin sio sir sis sna snb snc snf sni snn sno snr sns soa sob soc sof soi son soo sor sos sr- sra srb src srf sri srn sro srr srs ss- ssa ssb ssc ssf ssi ssn sso ssr sss