bbb bbe bbo bbs be- beb bee beo bes bev bob boe boo bos bov bsb bse bso bss bsv bvb bve bvo bvs bvv ebb ebe ebo ebs ebv eeb eee eeo ees eev eo- eob eoe eoo eos es- esb ese eso ess esv evb eve evo evs evv ob- obb obe obo obs obv oeb oee oeo oes oo- oob ooo oos oov os- osb ose oso oss osv ov- ovb ove ovo ovs ovv sbb sbe sbo sbs sbv se- seb see seo ses sev sob soe soo sos sov ss- ssb sse sso sss ssv svb sve svo svs svv v-e vbo vbs vbv veb vee veo ves vob voe voo vos vov vsb vse vso vss vsv vvb vvo vvs vvv