a-a a-b a-i aaa aab aag aai aao aap ab- aba abb abg abi abo abp ag- aga agb agg agi ago agp ai- aia aib aig aii aio aip aoa aob aog aoi aoo aop ap- apa apb apg api apo app b-p baa bab bag bai bao bap bba bbb bbg bbi bbo bbp bga bgb bgg bgi bgo bgp bi- bia bib big bii bio bip boa bob bog boi boo bop bpa bpb bpg bpi bpo bpp g-p gaa gab gag gai gao gap gba gbg gbi gbo gbp gga ggb ggg ggi ggo ggp gia gib gig gii gio gip goa gob gog goi goo gop gpa gpb gpg gpi gpo gpp ia- iaa iab iag iai iao iap iba ibb ibg ibi ibo ibp iga igb igg igi igo igp iia iib iii iio iip io- ioa iob iog ioi ioo iop ipa ipb ipg ipi ipo ipp o-i oaa oab oag oai oao oap ob- oba obb obg obi obo obp oga ogg ogi ogo ogp oia oib oii oio oip oo- ooa oob oog ooi ooo oop op- opa opb opg opi opo opp p-p paa pab pag pai pao pap pba pbb pbg pbi pbo pbp pga pgb pgg pgi pgo pgp pia pib pig pii pio pip poa pob pog poi poo pop ppa ppb ppg ppi ppo ppp