a-a aaa aaf aan aap aas af- afa aff afn afp afs an- ana anf ann anp ans ap- apa apf apn app aps as- asa asf asn asp ass faa faf fan fap fas ffa fff ffn ffp ffs fna fnf fnn fnp fns fpa fpn fpp fps fsa fsf fsn fsp fss naa naf nan nap nas nfa nff nfn nfp nfs nna nnf nnn nnp nns npa npf npn npp nps nsa nsf nsn nsp nss p-p paa paf pan pap pas pfa pff pfn pfp pfs pn- pna pnf pnn pnp pns ppa ppf ppn ppp pps ps- psa psf psn psp pss saa saf san sap sas sfa sff sfn sfp sfs sna snf snn snp sns spa spf spn spp sps ss- ssa ssf ssn ssp sss