-ic bbb bbc bbe bbi bbn bbo bcb bcc bce bci bcn bco be- beb bec bee bei ben beo bi- bib bic bie bii bin bio bnb bnc bne bni bnn bno bob boc boe boi bon boo c-- cbb cbc cbe cbi cbn cbo ccb ccc cce cci ccn cco ce- ceb cec cee cei cen ceo ci- cib cic cie cii cin cio cn- cnb cnc cne cni cnn cno co- cob coc coe coi con coo ebb ebc ebe ebi ebn ebo ec- ecb ecc ece eci ecn eco eeb eec eee een eeo eib eic eie eii ein eio en- enb enc ene eni enn eno eo- eob eoc eoe eoi eon eoo ibb ibc ibe ibi ibn ibo icb icc ice ici icn ico ie- iec iee iei ien iib iic iie iii iin iio in- inb inc ine ini inn ino io- iob ioc ioe ioi ion ioo n-i nbb nbc nbe nbi nbn nbo ncb ncc nce nci ncn nco ne- neb nec nee nei nen neo nib nic nie nii nin nio nnb nnc nne nni nnn nno no- nob noc noe noi non noo o-i ob- obb obc obe obi obn obo oc- ocb occ oci ocn oco oeb oec oee oei oen oeo oib oic oie oii oin oio on- onb onc one oni onn ono oo- oob ooc ooi oon ooo