a-a a-i aaa aai aap aar aas aax ai- aia aii aip air ais aix ap- apa api app apr aps apx ar- ara ari arp arr ars arx as- asa asi asp asr ass asx ax- axa axi axp axr axs axx ia- iaa iai iap iar ias iia iii iip iir iis iix ipa ipi ipp ipr ips ipx ir- ira iri irp irr irs irx is- isa isi isp isr iss ixi p-p paa pai pap par pas pax pia pii pip pir pis pix ppa ppi ppp ppr pps ppx pra pri prp prr prs prx ps- psa psi psp psr pss psx pxr pxs ra- raa rai rap rar ras rax ria rii rip rir ris rix rpa rpi rpp rpr rps rpx rra rri rrp rrr rrs rsa rsi rsp rsr rss rsx rxp rxr rxs saa sai sap sar sas sax sia sii sip sir sis six spa spi spp spr sps spx sr- sra sri srp srr srs srx ss- ssa ssi ssp ssr sss ssx sxi sxs xaa xap xar xas xia xii xis xix xpa xpp xps xrx xsa xsi xsp xss xxi xxp xxx