-er -ic a-a a-b a-c a-i aaa aab aac aae aag aai aao aar aas ab- aba abb abc abe abg abi abo abr abs ac- aca acb acc ace acg aci aco acr acs aea aeb aec aee aeg aei aeo aer aes ag- aga agb agc age agg agi ago agr ags ai- aia aib aic aie aig aii aio air ais aoa aob aoc aoe aog aoi aoo aor aos ar- ara arb arc are arg ari aro arr ars as- asa asb asc ase asg asi aso asr ass baa bab bac bae bag bai bao bar bas bba bbb bbc bbe bbg bbi bbo bbr bbs bca bcb bcc bce bcg bci bco bcr bcs be- bea beb bec bee beg bei beo ber bes bga bgb bgc bge bgg bgi bgo bgr bgs bi- bia bib bic bie big bii bio bir bis boa bob boc boe bog boi boo bor bos bra brb bre brg bri bro brr brs bsa bsb bsc bse bsg bsi bso bsr bss c-- caa cab cac cae cag cai cao car cas cba cbb cbc cbe cbg cbi cbo cbr cbs cca ccb ccc cce ccg cci cco ccr ccs ce- cea ceb cec cee ceg cei ceo cer ces cga cgb cgc cge cgg cgi cgo cgr cgs ci- cia cib cic cie cig cii cio cir cis co- coa cob coc coe cog coi coo cor cos cra crb crc cre crg cri cro crr crs csa csb csc cse csg csi cso csr css eaa eab eac eae eag eai eao ear eas eba ebb ebc ebe ebg ebi ebo ebr ebs ec- eca ecb ecc ece ecg eci eco ecr ecs eea eeb eec eee eeg eeo eer ees ega egb egc ege egg egi ego egr egs eia eib eic eie eig eii eio eir eis eo- eoa eob eoc eoe eog eoi eoo eor eos era erb erc ere erg eri ero err ers es- esa esb esc ese esg esi eso esr ess gaa gab gac gae gag gai gao gar gas gba gbc gbe gbg gbi gbo gbr gbs gca gcb gcc gce gcg gci gco gcr gcs ge- gea geb gec gee geg gei geo ger ges gga ggb ggc ggg ggi ggo ggr ggs gia gib gic gie gig gii gio gir gis goa gob goc goe gog goi goo gor gos gra grb grc gre grg gri gro grr grs gsa gsb gsc gse gsg gsi gso gsr gss ia- iaa iab iac iae iag iai iao iar ias iba ibb ibc ibe ibg ibi ibo ibr ibs ica icb icc ice icg ici ico icr ics ie- iea iec iee ieg iei ier ies iga igb igc ige igg igi igo igr igs iia iib iic iie iii iio iir iis io- ioa iob ioc ioe iog ioi ioo ior ios ir- ira irb irc ire irg iri iro irr irs is- isa isb isc ise isg isi iso isr iss o-i oaa oab oac oae oag oai oao oar oas ob- oba obb obc obe obg obi obo obr obs oc- oca ocb occ ocg oci oco ocr ocs oea oeb oec oee oeg oei oeo oer oes oga ogc oge ogg ogi ogo ogs oia oib oic oie oii oio oir ois oo- ooa oob ooc oog ooi ooo oor oos or- ora orb orc ore org ori oro orr ors os- osa osb osc ose osg osi oso osr oss ra- raa rab rac rae rag rai rao rar ras rba rbb rbc rbe rbg rbi rbo rbr rbs rca rcb rcc rce rcg rci rco rcr rcs re- rea reb rec ree reg rei reo rer res rga rgb rgc rge rgg rgi rgo rgr rgs ria rib ric rie rig rii rio rir ris roa rob roc roe rog roi roo ror ros rra rrb rrc rrg rri rrr rrs rsa rsb rsc rse rsg rsi rso rsr rss saa sab sac sae sag sai sao sar sas sba sbb sbc sbe sbg sbi sbo sbr sbs sca scb scc sce scg sci sco scr scs se- sea seb sec see seg sei seo ser ses sga sgb sgc sge sgg sgi sgo sgr sgs sia sib sic sie sig sii sio sir sis soa sob soc soe sog soi soo sor sos sr- sra srb src sre srg sri sro srr srs ss- ssa ssb ssc sse ssg ssi sso ssr sss