-er bbb bbe bbf bbg bbl bbr bbs be- beb bee bef beg bel ber bes bfb bfe bff bfg bfl bfr bfs bgb bge bgf bgg bgl bgr bgs blb ble blf blg bll blr bls brb bre brf brg brl brr brs bsb bse bsf bsg bsl bsr bss ebb ebe ebf ebg ebl ebr ebs eeb eee eef eeg eel eer ees ef- efb efe eff efg efl efr efs egb ege egf egg egl egr egs elb ele elf elg ell elr els erb ere erf erg erl err ers es- esb ese esf esg esl esr ess fbb fbe fbf fbg fbl fbr fbs feb fee fef feg fel fer fes ffe fff ffg ffl ffr ffs fgb fge fgf fgg fgl fgr fgs flb fle flf flg fll flr fls frb fre frf frg frl frr frs fsb fse fsf fsg fsl fsr fss gbe gbf gbg gbl gbr gbs ge- geb gee gef geg gel ger ges gfb gfe gff gfl gfr gfs ggb ggg ggr ggs glb gle glf glg gll glr gls grb gre grf grg grl grr grs gsb gse gsf gsg gsl gsr gss lbb lbe lbf lbg lbl lbr lbs leb lee lef leg lel ler les lfb lfe lff lfg lfl lfr lfs lgb lge lgf lgg lgl lgr lgs llb lle llf llg lll llr lls lrb lrf lrg lrr lrs lsb lse lsf lsg lsl lsr lss rbb rbe rbf rbg rbl rbr rbs re- reb ree ref reg rel rer res rfb rfe rff rfg rfl rfr rfs rgb rge rgf rgg rgr rgs rle rlf rlg rll rlr rls rrb rrf rrg rrl rrr rrs rsb rse rsf rsg rsl rsr rss sbb sbe sbf sbg sbl sbr sbs se- seb see sef seg sel ser ses sfb sfe sff sfg sfl sfr sfs sgb sge sgf sgg sgl sgr sgs slb sle slf slg sll slr sls sr- srb sre srf srg srl srr srs ss- ssb sse ssf ssg ssl ssr sss