-ic bbb bbc bbe bbi bbn bbt bcb bcc bce bci bcn bct be- beb bec bee bei ben bet bi- bib bic bie bii bin bit bnb bnc bne bni bnn bnt btb btc bte bti btn btt c-- cbb cbc cbe cbi cbn cbt ccb ccc cce cci ccn cct ce- ceb cec cee cei cen cet ci- cib cic cie cii cin cit cn- cnb cnc cne cni cnn cnt ctb ctc cte cti ctn ctt ebb ebc ebe ebi ebn ebt ec- ecb ecc ece eci ecn ect eeb eec eee een eet eib eic eie eii ein eit en- enb enc ene eni enn ent etb etc ete eti etn ett ibb ibc ibe ibi ibn ibt icb icc ice ici icn ict ie- iec iee iei ien iet iib iic iie iii iin iit in- inb inc ine ini inn int itb itc ite iti itn itt n-i nbb nbc nbe nbi nbn nbt ncb ncc nce nci ncn nct ne- neb nec nee nei nen net nib nic nie nii nin nit nnb nnc nne nni nnn nnt ntb ntc nte nti ntn ntt tbb tbc tbe tbi tbn tbt tcb tcc tce tci tcn tct te- teb tec tee tei ten tet tib tic tie tii tin tit tnb tnc tne tni tnn tnt ttb ttc tte tti ttn ttt