-er -ic bbb bbc bbe bbg bbi bbk bbr bbt bcb bcc bce bcg bci bck bcr bct be- beb bec bee beg bei bek ber bet bgb bgc bge bgg bgi bgk bgr bgt bi- bib bic bie big bii bik bir bit bkb bkc bke bkg bkk bkr bkt brb bre brg bri brk brr brt btb btc bte btg bti btk btr btt c-- cbb cbc cbe cbg cbi cbk cbr cbt ccb ccc cce ccg cci cck ccr cct ce- ceb cec cee ceg cei cek cer cet cgb cgc cge cgg cgi cgr cgt ci- cib cic cie cig cii cik cir cit ckb ckc cki ckt crb crc cre crg cri crk crr crt ctb ctc cte ctg cti ctk ctr ctt ebb ebc ebe ebg ebi ebk ebr ebt ec- ecb ecc ece ecg eci eck ecr ect eeb eec eee eeg eek eer eet egb egc ege egg egi egr egt eib eic eie eig eii eik eir eit ekb ekc eke ekg eki ekr ekt erb erc ere erg eri erk err ert etb etc ete etg eti etk etr ett gbc gbe gbg gbi gbk gbr gbt gcb gcc gce gcg gci gck gcr gct ge- geb gec gee geg gei gek ger get ggb ggc ggg ggi ggr ggt gib gic gie gig gii gik gir git gkb gkt grb grc gre grg gri grk grr grt gtb gtc gte gtg gti gtk gtr gtt ibb ibc ibe ibg ibi ibk ibr ibt icb icc ice icg ici ick icr ict ie- iec iee ieg iei iek ier iet igb igc ige igg igi igk igr igt iib iic iie iii iir iit ikb ikc ike iki ikk ikr ikt ir- irb irc ire irg iri irk irr irt itb itc ite itg iti itk itt k-t kbb kbc kbe kbi kbk kbr kcb kcc kce kcg kci kck kcr kct ke- keb kec kee keg kei kek ker ket kgb kgc kgi kib kic kie kig kii kik kir kit kkb kkc kke kki kkk kkr kkt krc krg kri krk krr krt ktb ktc kte ktg ktk ktr ktt rbb rbc rbe rbg rbi rbk rbr rbt rcb rcc rce rcg rci rcr rct re- reb rec ree reg rei rek rer ret rgb rgc rge rgg rgi rgk rgr rgt rib ric rie rig rii rik rir rit rkb rkc rke rkg rkk rkt rrb rrc rrg rri rrk rrr rrt rtb rtc rte rtg rti rtk rtr rtt tbb tbc tbe tbg tbi tbk tbr tbt tcb tcc tce tcg tci tck tcr tct te- teb tec tee teg tei tek ter tet tgb tgc tge tgg tgi tgk tgr tgt tib tic tie tig tii tik tir tit tkb tkc tke tkg tkk tkr tkt trb trc tre trg tri trk trr trt ttb ttc tte ttg tti ttk ttr ttt