a-a aaa aan aao aap aas aax an- ana ann ano anp ans anx aoa aon aoo aop aos aox ap- apa apn apo app aps apx as- asa asn aso asp ass asx ax- axa axn axo axp axs axx naa nan nao nap nas nax nna nnn nno nnp nns no- noa non noo nop nos nox npa npn npo npp nps nsa nsn nso nsp nss nsx oaa oan oao oap oas oax on- ona onn ono onp ons onx oo- ooa oon ooo oop oos oox op- opa opn opo opp ops opx os- osa osn oso osp oss osx ox- oxa oxn oxo oxx p-p paa pan pao pap pas pax pn- pna pnn pno pnp pns pnx poa pon poo pop pos pox ppa ppn ppo ppp pps ppx ps- psa psn pso psp pss psx pxs saa san sao sap sas sax sna snn sno snp sns soa son soo sop sos sox spa spn spo spp sps spx ss- ssa ssn sso ssp sss ssx sxn sxs xaa xan xap xas xna xno xns xoa xon xoo xop xos xox xpa xpn xpo xpp xps xsa xsp xss xxo xxp xxx