a-a aaa aaf aag aah aan af- afa aff afg afh afn ag- aga agf agg agh agn aha ahf ahg ahh ahn an- ana anf ang anh ann faa faf fag fah fan ffa fff ffg ffh ffn fga fgf fgg fgh fgn fha fhf fhg fhh fhn fna fnf fng fnh fnn gaa gaf gag gah gan gfa gff gfh gga ggg ggh ggn gha ghg ghh ghn gna gnf gnn haa haf hag hah han hfa hff hfg hfh hfn hga hgf hgg hgh hgn hha hhf hhg hhh hhn hna hnf hng hnh hnn naa naf nag nah nan nfa nff nfn nga ngf ngg ngh ngn nha nhf nhg nhh nhn nna nnf nng nnh nnn