a-a aaa aan aap aar aas an- ana ann anp anr ans ap- apa apn app apr aps ar- ara arn arp arr ars as- asa asn asp asr ass naa nan nap nar nas nna nnn nnp nns npa npn npp npr nps nra nrn nrp nrr nrs nsa nsn nsp nsr nss p-p paa pan pap par pas pn- pna pnn pnp pnr pns ppa ppn ppp ppr pps pra prn prp prr prs ps- psa psn psp psr pss ra- raa ran rap rar ras rna rnn rnp rnr rns rpa rpn rpp rpr rps rra rrn rrp rrr rrs rsa rsn rsp rsr rss saa san sap sar sas sna snn snp snr sns spa spn spp spr sps sr- sra srn srp srr srs ss- ssa ssn ssp ssr sss