a-a a-c aaa aac aae aan aap aas ac- aca acc ace acn acp acs aea aec aee aen aep aes an- ana anc ane ann anp ans ap- apa apc ape apn app aps as- asa asc ase asn asp ass c-- caa cac cae can cap cas cca ccc cce ccn ccp ccs ce- cea cec cee cen cep ces cn- cna cnc cne cnn cnp cns cpa cpc cpe cpn cpp cps csa csc cse csn csp css eaa eac eae ean eap eas ec- eca ecc ece ecn ecs eea eec eee een eep ees en- ena enc ene enn enp ens ep- epa epc epe epn epp eps es- esa esc ese esn esp ess naa nac nae nan nap nas nca ncc nce ncn ncp ncs ne- nea nec nee nen nep nes nna nnc nne nnn nnp nns npa npc npe npn npp nps nsa nsc nse nsn nsp nss p-p paa pac pae pan pap pas pca pcc pce pcn pcp pcs pea pec pee pen pep pes pn- pna pnc pne pnn pnp pns ppa ppc ppe ppn ppp pps ps- psa psc pse psn psp pss saa sac sae san sap sas sca scc sce scn scp scs se- sea sec see sen sep ses sna snc sne snn snp sns spa spc spe spn spp sps ss- ssa ssc sse ssn ssp sss