a-a aaa aan aao aap aar aas aax an- ana ann ano anp anr ans anx aoa aon aoo aop aor aos aox ap- apa apn apo app apr aps apx ar- ara arn aro arp arr ars arx as- asa asn aso asp asr ass asx ax- axa axn axo axp axr axs axx naa nan nao nap nar nas nax nna nnn nno nnp nns no- noa non noo nop nor nos nox npa npn npo npp npr nps nra nrn nro nrp nrr nrs nrx nsa nsn nso nsp nsr nss nsx oaa oan oao oap oar oas oax on- ona onn ono onp onr ons onx oo- ooa oon ooo oop oor oos oox op- opa opn opo opp opr ops opx or- ora orn oro orp orr ors orx os- osa osn oso osp osr oss osx ox- oxa oxn oxo oxx p-p paa pan pao pap par pas pax pn- pna pnn pno pnp pnr pns pnx poa pon poo pop por pos pox ppa ppn ppo ppp ppr pps ppx pra prn pro prp prr prs prx ps- psa psn pso psp psr pss psx pxr pxs ra- raa ran rao rap rar ras rax rna rnn rno rnp rnr rns roa ron roo rop ror ros rox rpa rpn rpo rpp rpr rps rpx rra rrn rrp rrr rrs rsa rsn rso rsp rsr rss rsx rxp rxr rxs saa san sao sap sar sas sax sna snn sno snp snr sns soa son soo sop sor sos sox spa spn spo spp spr sps spx sr- sra srn sro srp srr srs srx ss- ssa ssn sso ssp ssr sss ssx sxn sxs xaa xan xap xar xas xna xno xns xoa xon xoo xop xor xos xox xpa xpn xpo xpp xps xrx xsa xsp xss xxo xxp xxx