-ic a-a a-b a-c a-i aaa aab aac aai aan aao aap ab- aba abb abc abi abn abo abp ac- aca acb acc aci acn aco acp ai- aia aib aic aii ain aio aip an- ana anb anc ani ann ano anp aoa aob aoc aoi aon aoo aop ap- apa apb apc api apn apo app b-p baa bab bac bai ban bao bap bba bbb bbc bbi bbn bbo bbp bca bcb bcc bci bcn bco bcp bi- bia bib bic bii bin bio bip bna bnb bnc bni bnn bno bnp boa bob boc boi bon boo bop bpa bpb bpc bpi bpn bpo bpp c-- caa cab cac cai can cao cap cba cbb cbc cbi cbn cbo cbp cca ccb ccc cci ccn cco ccp ci- cia cib cic cii cin cio cip cn- cna cnb cnc cni cnn cno cnp co- coa cob coc coi con coo cop cpa cpb cpc cpi cpn cpo cpp ia- iaa iab iac iai ian iao iap iba ibb ibc ibi ibn ibo ibp ica icb icc ici icn ico icp iia iib iic iii iin iio iip in- ina inb inc ini inn ino inp io- ioa iob ioc ioi ion ioo iop ipa ipb ipc ipi ipn ipo ipp n-i naa nab nac nai nan nao nap nba nbb nbc nbi nbn nbo nbp nca ncb ncc nci ncn nco ncp nia nib nic nii nin nio nip nna nnb nnc nni nnn nno nnp no- noa nob noc noi non noo nop npa npb npc npi npn npo npp o-i oaa oab oac oai oan oao oap ob- oba obb obc obi obn obo obp oc- oca ocb occ oci ocn oco ocp oia oib oic oii oin oio oip on- ona onb onc oni onn ono onp oo- ooa oob ooc ooi oon ooo oop op- opa opb opc opi opn opo opp p-p paa pab pac pai pan pao pap pba pbb pbc pbi pbn pbo pbp pca pcb pcc pci pcn pco pcp pia pib pic pii pin pio pip pn- pna pnb pnc pni pnn pno pnp poa pob poc poi pon poo pop ppa ppb ppc ppi ppn ppo ppp