a-a a-t aaa aan aap aas aat an- ana ann anp ans ant ap- apa apn app aps apt as- asa asn asp ass ast at- ata atn atp ats att naa nan nap nas nat nna nnn nnp nns nnt npa npn npp nps npt nsa nsn nsp nss nst nta ntn ntp nts ntt p-p paa pan pap pas pat pn- pna pnn pnp pns pnt ppa ppn ppp pps ppt ps- psa psn psp pss pst pt- pta ptn ptp pts ptt saa san sap sas sat sna snn snp sns snt spa spn spp sps spt ss- ssa ssn ssp sss sst sta stn stp sts stt taa tan tap tas tat tna tnn tnp tns tnt tpa tpn tpp tps tpt tsa tsn tsp tss tst tta ttn ttp tts ttt