-ic a-a a-b a-c a-i aaa aab aac aae aai aak aam aan ab- aba abb abc abe abi abk abm abn ac- aca acb acc ace aci ack acm acn aea aeb aec aee aei aek aem aen ai- aia aib aic aie aii aik aim ain aka akb akc ake aki akk akm akn ama amb amc ame ami amk amm amn an- ana anb anc ane ani ank anm ann baa bab bac bae bai bak bam ban bba bbb bbc bbe bbi bbk bbm bbn bca bcb bcc bce bci bck bcm bcn be- bea beb bec bee bei bek bem ben bi- bia bib bic bie bii bik bim bin bka bkb bkc bke bkk bkm bkn bma bmb bmc bme bmi bmk bmm bmn bna bnb bnc bne bni bnk bnn c-- caa cab cac cae cai cak cam can cba cbb cbc cbe cbi cbk cbm cbn cca ccb ccc cce cci cck ccm ccn ce- cea ceb cec cee cei cek cem cen ci- cia cib cic cie cii cik cim cin cka ckb ckc cki ckm cma cmb cmc cme cmi cmk cmm cmn cn- cna cnb cnc cne cni cnm cnn eaa eab eac eae eai eak eam ean eba ebb ebc ebe ebi ebk ebm ebn ec- eca ecb ecc ece eci eck ecm ecn eea eeb eec eee eek eem een eia eib eic eie eii eik eim ein eka ekb ekc eke eki em- ema emb emc eme emi emk emm emn en- ena enb enc ene eni enk enm enn ia- iaa iab iac iae iai iam ian iba ibb ibc ibe ibi ibk ibm ibn ica icb icc ice ici ick icm icn ie- iea iec iee iei iek iem ien iia iib iic iie iii iim iin ika ikb ikc ike iki ikk im- ima imb imc ime imi imm imn in- ina inb inc ine ini ink inm inn ka- kaa kab kac kae kai kak kam kan kba kbb kbc kbe kbi kbk kbm kbn kca kcb kcc kce kci kck kcm kcn ke- kea keb kec kee kei kek kem ken kia kib kic kie kii kik kim kin kkb kkc kke kki kkk kkm kkn kma kmb kmc kme kmi kmk kmm kn- kna knc kne kni knk knm knn maa mab mac mae mai mak mam man mba mbb mbc mbe mbi mbk mbm mc- mca mcb mcc mce mci mck mcm mcn mea meb mec mee mei mek mem men mi- mia mib mic mie mii mik mim min mka mkb mkc mke mkk mkm mkn mma mmb mmc mme mmi mmk mmm mmn mna mnb mnc mne mni mnk mnm mnn n-i naa nab nac nae nai nak nam nan nba nbb nbc nbe nbi nbk nbm nbn nca ncb ncc nce nci nck ncm ncn ne- nea neb nec nee nei nek nem nen nia nib nic nie nii nik nim nin nka nkc nke nki nkk nkm nkn nma nmb nmc nme nmi nmk nmm nmn nna nnb nnc nne nni nnk nnm nnn