bbb bbe bbn bbo bbs be- beb bee ben beo bes bnb bne bnn bno bns bob boe bon boo bos bsb bse bsn bso bss ebb ebe ebn ebo ebs eeb eee een eeo ees en- enb ene enn eno ens eo- eob eoe eon eoo eos es- esb ese esn eso ess nbb nbe nbn nbo nbs ne- neb nee nen neo nes nnb nne nnn nno nns no- nob noe non noo nos nsb nse nsn nso nss ob- obb obe obn obo obs oeb oee oen oeo oes on- onb one onn ono ons oo- oob oon ooo oos os- osb ose osn oso oss sbb sbe sbn sbo sbs se- seb see sen seo ses snb sne snn sno sns sob soe son soo sos ss- ssb sse ssn sso sss