a-a aaa aaf aan aao aap aar af- afa aff afn afo afp afr an- ana anf ann ano anp anr aoa aof aon aoo aop aor ap- apa apf apn apo app apr ar- ara arf arn aro arp arr faa faf fan fao fap far ffa fff ffn ffo ffp ffr fna fnf fnn fnp fnr foa fof fon foo fop for fpa fpn fpo fpp fpr fra frf frn fro frp frr naa naf nan nao nap nar nfa nff nfn nfo nfp nfr nna nnf nnn nno nnp no- noa nof non noo nop nor npa npf npn npo npp npr nra nrf nrn nro nrp nrr oaa oaf oan oao oap oar of- ofa off ofn ofo ofp ofr on- ona onf onn ono onp onr oo- ooa oof oon ooo oop oor op- opa opf opn opo opp opr or- ora orf orn oro orp orr p-p paa paf pan pao pap par pfa pff pfn pfo pfp pfr pn- pna pnf pnn pno pnp pnr poa pof pon poo pop por ppa ppf ppn ppo ppp ppr pra prf prn pro prp prr ra- raa raf ran rao rap rar rfa rff rfn rfo rfp rfr rna rnn rno rnp rnr roa rof ron roo rop ror rpa rpf rpn rpo rpp rpr rra rrf rrn rrp rrr