-er -ic a-a a-c a-i aaa aac aae aai aao aar aax ac- aca acc ace aci aco acr acx aea aec aee aei aeo aer aex ai- aia aic aie aii aio air aix aoa aoc aoe aoi aoo aor aox ar- ara arc are ari aro arr arx ax- axa axe axi axo axr axx c-- caa cac cae cai cao car cax cca ccc cce cci cco ccr ccx ce- cea cec cee cei ceo cer cex ci- cia cic cie cii cio cir cix co- coa coc coe coi coo cor cox cra crc cre cri cro crr crx cxc cxi cxo cxr cxx eaa eac eae eai eao ear eax ec- eca ecc ece eci eco ecr ecx eea eec eee eeo eer eex eia eic eie eii eio eir eix eo- eoa eoc eoe eoi eoo eor era erc ere eri ero err ex- exa exc exe exi exo exr exx ia- iaa iac iae iai iao iar ica icc ice ici ico icr ie- iea iec iee iei ier iex iia iic iie iii iio iir iix io- ioa ioc ioe ioi ioo ior ir- ira irc ire iri iro irr irx ixc ixe ixi o-i oaa oac oae oai oao oar oax oc- oca occ oci oco ocr ocx oea oec oee oei oeo oer oex oia oic oie oii oio oir oo- ooa ooc ooi ooo oor oox or- ora orc ore ori oro orr orx ox- oxa oxc oxi oxo oxx ra- raa rac rae rai rao rar rax rca rcc rce rci rco rcr rcx re- rea rec ree rei reo rer rex ria ric rie rii rio rir rix roa roc roe roi roo ror rox rra rrc rri rrr rxr xaa xac xar xci xcr xcx xee xer xex xia xic xie xii xio xix xoa xoc xoi xoo xor xox xrc xrx xxi xxo xxx