bbb bbd bbo bbr bbt bby bdb bdd bdo bdr bdt bdy bob bod boo bor bot boy brb brd bro brr brt bry btb btd bto btr btt bty by- byd byo byr byt dbb dbd dbo dbr dbt dby ddb ddd ddo ddr ddt ddy dob dod doo dor dot doy drb drd dro drr drt dry dtb dtd dto dtr dtt dty dy- dyb dyd dyo dyr dyy ob- obb obd obo obr obt oby odb odd odo odr odt oo- oob ood ooo oor oot or- orb ord oro orr ort ory ot- otb otd oto otr ott oyd oyo rbb rbd rbo rbr rbt rdb rdd rdo rdr rdt rdy rob rod roo ror rot roy rrb rrd rrr rrt rtb rtd rto rtr rtt rty ry- ryd ryo ryr ryy tbb tbd tbo tbr tbt tdb tdd tdo tdr tdt tdy to- tob tod too tor tot toy trb trd tro trr trt try ttb ttd tto ttr ttt tty tyd tyo tyr tyt ybr yby ydo ydt ydy yob yod yoo yor yot yoy yro yrt ytd yto ytr ytt yyb yyt yyy