-ic bbb bbc bbe bbi bbk bbn bbo bcb bcc bce bci bck bcn bco be- beb bec bee bei bek ben beo bi- bib bic bie bii bik bin bio bkb bkc bke bkk bkn bko bnb bnc bne bni bnk bnn bno bob boc boe boi bok bon boo c-- cbb cbc cbe cbi cbk cbn cbo ccb ccc cce cci cck ccn cco ce- ceb cec cee cei cek cen ceo ci- cib cic cie cii cik cin cio ckb ckc cki cko cn- cnb cnc cne cni cnn cno co- cob coc coe coi cok con coo ebb ebc ebe ebi ebk ebn ebo ec- ecb ecc ece eci eck ecn eco eeb eec eee eek een eeo eib eic eie eii eik ein eio ekb ekc eke eki eko en- enb enc ene eni enk enn eno eo- eob eoc eoe eoi eok eon eoo ibb ibc ibe ibi ibk ibn ibo icb icc ice ici ick icn ico ie- iec iee iei iek ien iib iic iie iii iin iio ikb ikc ike iki ikk iko in- inb inc ine ini ink inn ino io- iob ioc ioe ioi ion ioo kbb kbc kbe kbi kbk kbn kbo kcb kcc kce kci kck kcn ke- keb kec kee kei kek ken keo kib kic kie kii kik kin kio kkb kkc kke kki kkk kkn kn- knc kne kni knk knn kno kob koc koe koi kok kon koo n-i nbb nbc nbe nbi nbk nbn nbo ncb ncc nce nci nck ncn nco ne- neb nec nee nei nek nen neo nib nic nie nii nik nin nio nkc nke nki nkk nkn nko nnb nnc nne nni nnk nnn nno no- nob noc noe noi nok non noo o-i ob- obb obc obe obi obk obn obo oc- ocb occ oci ock ocn oco oeb oec oee oei oen oeo oib oic oie oii oik oin oio okb okc oke oki okk oko on- onb onc one oni onk onn ono oo- oob ooc ooi ook oon ooo