-er a-a a-b a-i a-t aaa aab aae aai aak aan aar aat ab- aba abb abe abi abk abn abr abt aea aeb aee aei aek aen aer aet ai- aia aib aie aii aik ain air ait aka akb ake aki akk akn akr an- ana anb ane ani ank ann anr ant ar- ara arb are ari ark arn arr art at- ata atb ate ati atn atr att baa bab bae bai bak ban bar bat bba bbb bbe bbi bbk bbn bbr bbt be- bea beb bee bei bek ben ber bet bi- bia bib bie bii bik bin bir bit bka bkb bke bkk bkn bkr bkt bna bnb bne bni bnk bnn bnr bnt bra brb bre bri brk brn brr brt bta btb bte bti btk btn btr btt eaa eab eae eai eak ean ear eat eba ebb ebe ebi ebk ebn ebr ebt eea eeb eee eek een eer eet eia eib eie eii eik ein eir eit eka ekb eke eki ekr ekt en- ena enb ene eni enk enn enr ent era erb ere eri erk ern err ert eta etb ete eti etk etn etr ett ia- iaa iab iae iai ian iar iat iba ibb ibe ibi ibk ibn ibr ibt ie- iea iee iei iek ien ier iet iia iib iie iii iin iir iit ika ikb ike iki ikk ikr ikt in- ina inb ine ini ink inn inr int ir- ira irb ire iri irk irn irr irt ita itb ite iti itk itn itt k-t ka- kaa kab kae kai kak kan kar kat kba kbb kbe kbi kbk kbn kbr ke- kea keb kee kei kek ken ker ket kia kib kie kii kik kin kir kit kkb kke kki kkk kkn kkr kkt kn- kna kne kni knk knn knr knt kra kri krk krn krr krt kta ktb kte ktk ktn ktr ktt n-i naa nab nae nai nak nan nar nat nba nbb nbe nbi nbk nbn nbr nbt ne- nea neb nee nei nek nen ner net nia nib nie nii nik nin nir nit nka nke nki nkk nkn nkr nkt nna nnb nne nni nnk nnn nnt nra nrb nre nri nrk nrn nrr nrt nta ntb nte nti ntk ntn ntr ntt ra- raa rab rae rai rak ran rar rat rba rbb rbe rbi rbk rbn rbr rbt re- rea reb ree rei rek ren rer ret ria rib rie rii rik rin rir rit rkb rke rkk rkt rna rnb rni rnn rnr rnt rra rrb rri rrk rrn rrr rrt rta rtb rte rti rtk rtn rtr rtt taa tab tae tai tak tan tar tat tba tbb tbe tbi tbk tbn tbr tbt te- tea teb tee tei tek ten ter tet tia tib tie tii tik tin tir tit tka tkb tke tkk tkr tkt tna tnb tne tni tnk tnn tnr tnt tra trb tre tri trk trn trr trt tta ttb tte tti ttk ttn ttr ttt