-er -ic bbb bbc bbe bbf bbi bbk bbr bcb bcc bce bcf bci bck bcr be- beb bec bee bef bei bek ber bfb bfc bfe bff bfi bfr bi- bib bic bie bif bii bik bir bkb bkc bke bkf bkk bkr brb bre brf bri brk brr c-- cbb cbc cbe cbf cbi cbk cbr ccb ccc cce ccf cci cck ccr ce- ceb cec cee cef cei cek cer cfb cfc cfe cff cfi cfk cfr ci- cib cic cie cif cii cik cir ckb ckc cki crb crc cre crf cri crk crr ebb ebc ebe ebf ebi ebk ebr ec- ecb ecc ece ecf eci eck ecr eeb eec eee eef eek eer ef- efb efc efe eff efi efr eib eic eie eif eii eik eir ekb ekc eke ekf eki ekr erb erc ere erf eri erk err fbb fbc fbe fbf fbi fbk fbr fcb fcc fce fcf fci fck fcr feb fec fee fef fei fek fer ffc ffe fff ffi ffk ffr fib fic fie fif fii fik fir fkb fkc fkf fki fkk frb frc fre frf fri frk frr i-f ibb ibc ibe ibf ibi ibk ibr icb icc ice icf ici ick icr ie- iec iee ief iei iek ier ifb ifc ife iff ifi ifr iib iic iie iif iii iir ikb ikc ike ikf iki ikk ikr ir- irb irc ire irf iri irk irr kbb kbc kbe kbf kbi kbk kbr kcb kcc kce kci kck kcr ke- keb kec kee kef kei kek ker kfc kff kfi kib kic kie kif kii kik kir kkb kkc kke kki kkk kkr krc krf kri krk krr rbb rbc rbe rbf rbi rbk rbr rcb rcc rce rcf rci rcr re- reb rec ree ref rei rek rer rfb rfc rfe rff rfi rfk rfr rib ric rie rif rii rik rir rkb rkc rke rkf rkk rrb rrc rrf rri rrk rrr