a-a a-b aaa aab aad aae aak aam aan ab- aba abb abd abe abk abm abn ad- ada adb add ade adk adm adn aea aeb aed aee aek aem aen aka akb akd ake akk akm akn ama amb amd ame amk amm amn an- ana anb and ane ank anm ann baa bab bad bae bak bam ban bba bbb bbd bbe bbk bbm bbn bda bdb bdd bde bdk bdm be- bea beb bed bee bek bem ben bka bkb bke bkk bkm bkn bma bmb bmd bme bmk bmm bmn bna bnb bnd bne bnk bnn daa dab dad dae dak dam dan dba dbb dbd dbe dbk dbm dbn dda ddb ddd dde ddk ddm ddn de- dea deb ded dee dek dem den dka dkb dke dkk dkm dma dmb dmd dme dmk dmm dmn dna dnb dnd dne dnk dnm dnn eaa eab ead eae eak eam ean eba ebb ebd ebe ebk ebm ebn ed- eda edb edd ede edk edm edn eea eeb eed eee eek eem een eka ekb ekd eke em- ema emb emd eme emk emm emn en- ena enb end ene enk enm enn ka- kaa kab kad kae kak kam kan kba kbb kbd kbe kbk kbm kbn kda kdb kde kdk kdm ke- kea keb ked kee kek kem ken kkb kke kkk kkm kkn kma kmb kmd kme kmk kmm kn- kna knd kne knk knm knn maa mab mad mae mak mam man mba mbb mbd mbe mbk mbm mda mdb mdd mde mdk mdm mdn mea meb med mee mek mem men mka mkb mkd mke mkk mkm mkn mma mmb mmd mme mmk mmm mmn mna mnb mne mnk mnm mnn naa nab nad nae nak nam nan nba nbb nbd nbe nbk nbm nbn nda ndb ndd nde ndk ndm ndn ne- nea neb ned nee nek nem nen nka nke nkk nkm nkn nma nmb nmd nme nmk nmm nmn nna nnb nne nnk nnm nnn