-er -th a-a a-b a-c a-t aaa aab aac aae aah aar aat ab- aba abb abc abe abh abr abt ac- aca acb acc ace ach acr act aea aeb aec aee aeh aer aet aha ahb ahc ahe ahh ahr aht ar- ara arb arc are arh arr art at- ata atb atc ate ath atr att baa bab bac bae bah bar bat bba bbb bbc bbe bbh bbr bbt bca bcb bcc bce bch bcr bct be- bea beb bec bee beh ber bet bha bhb bhc bhe bhh bhr bht bra brb bre brh brr brt bta btb btc bte bth btr btt c-- caa cab cac cae cah car cat cba cbb cbc cbe cbh cbr cbt cca ccb ccc cce cch ccr cct ce- cea ceb cec cee ceh cer cet ch- cha chb chc che chh chr cht cra crb crc cre crh crr crt cta ctb ctc cte cth ctr ctt eaa eab eac eae eah ear eat eba ebb ebc ebe ebh ebr ebt ec- eca ecb ecc ece ech ecr ect eea eeb eec eee eer eet eha ehb ehc ehe ehh ehr eht era erb erc ere erh err ert eta etb etc ete eth etr ett haa hab hac hae hah har hat hba hbb hbc hbe hbh hbr hbt hca hcb hcc hce hch hcr hct he- hea heb hec hee heh her het hha hhb hhc hhe hhh hhr hht hr- hra hrb hrc hre hrh hrr hrt hta htb htc hte hth htr htt ra- raa rab rac rae rah rar rat rba rbb rbc rbe rbh rbr rbt rca rcb rcc rce rch rcr rct re- rea reb rec ree reh rer ret rh- rha rhb rhc rhe rhh rhr rht rra rrb rrc rrh rrr rrt rta rtb rtc rte rtr rtt taa tab tac tae tah tar tat tba tbb tbc tbe tbh tbr tbt tca tcb tcc tce tch tcr tct te- tea teb tec tee teh ter tet th- tha thb thc the thh thr tht tra trb trc tre trh trr trt tta ttb ttc tte tth ttr ttt