-er a-a a-c aaa aac aae aaf aan aar ac- aca acc ace acf acn acr aea aec aee aef aen aer af- afa afc afe aff afn afr an- ana anc ane anf ann anr ar- ara arc are arf arn arr c-- caa cac cae caf can car cca ccc cce ccf ccn ccr ce- cea cec cee cef cen cer cfa cfc cfe cff cfn cfr cn- cna cnc cne cnf cnn cnr cra crc cre crf crn crr eaa eac eae eaf ean ear ec- eca ecc ece ecf ecn ecr eea eec eee eef een eer ef- efa efc efe eff efr en- ena enc ene enf enn enr era erc ere erf ern err faa fac fae faf fan far fca fcc fce fcf fcn fcr fea fec fee fef fen fer ffa ffc ffe fff ffn ffr fna fnc fne fnf fnn fnr fra frc fre frf frn frr naa nac nae naf nan nar nca ncc nce ncf ncn ncr ne- nea nec nee nef nen ner nfa nfc nfe nff nfn nfr nna nnc nne nnf nnn nra nrc nre nrf nrn nrr ra- raa rac rae raf ran rar rca rcc rce rcf rcn rcr re- rea rec ree ref ren rer rfa rfc rfe rff rfn rfr rna rnc rnn rnr rra rrc rrf rrn rrr