bbb bbe bbk bbn bbo bbs be- beb bee bek ben beo bes bkb bke bkk bkn bko bks bnb bne bnk bnn bno bns bob boe bok bon boo bos bsb bse bsk bsn bso bss ebb ebe ebk ebn ebo ebs eeb eee eek een eeo ees ekb eke eko eks en- enb ene enk enn eno ens eo- eob eoe eok eon eoo eos es- esb ese esk esn eso ess kbb kbe kbk kbn kbo kbs ke- keb kee kek ken keo kes kkb kke kkk kkn kks kn- kne knk knn kno kob koe kok kon koo kos ksb kse ksk ksn kso kss nbb nbe nbk nbn nbo nbs ne- neb nee nek nen neo nes nke nkk nkn nko nks nnb nne nnk nnn nno nns no- nob noe nok non noo nos nsb nse nsk nsn nso nss ob- obb obe obk obn obo obs oeb oee oen oeo oes okb oke okk oko oks on- onb one onk onn ono ons oo- oob ook oon ooo oos os- osb ose osk osn oso oss sbb sbe sbk sbn sbo sbs se- seb see sek sen seo ses sk- skb ske skk sko sks snb sne snk snn sno sns sob soe sok son soo sos ss- ssb sse ssk ssn sso sss