-er -ic c-- ccc ccd cce cci cck ccr ccx cdc cdd cde cdi cdk cdr cdx ce- cec ced cee cei cek cer cex ci- cic cid cie cii cik cir cix ckc ckd cki ckx crc crd cre cri crk crr crx cxc cxi cxk cxr cxx dcc dcd dce dci dck dcr dcx ddc ddd dde ddi ddk ddr ddx de- dec ded dee dei dek der dex di- dic did die dii dik dir dix dkc dke dki dkk dkr dkx drc drd dre dri drk drr drx dxc dxd dxi dxr dxx ec- ecc ecd ece eci eck ecr ecx ed- edc edd ede edi edk edr edx eec eed eee eek eer eex eic eid eie eii eik eir eix ekc ekd eke eki ekr erc erd ere eri erk err ex- exc exd exe exi exr exx i-d icc icd ice ici ick icr idc idd ide idi idk idr idx ie- iec ied iee iei iek ier iex iic iid iie iii iir iix ikc ike iki ikk ikr ikx ir- irc ird ire iri irk irr irx ixc ixe ixi kcc kcd kce kci kck kcr kcx kdc kde kdk kdr kdx ke- kec ked kee kei kek ker kex kic kid kie kii kik kir kix kkc kke kki kkk kkr krc krd kri krk krr rcc rcd rce rci rcr rcx rdc rdd rde rdi rdr rdx re- rec red ree rei rek rer rex ric rid rie rii rik rir rix rkc rke rkk rrc rrd rri rrk rrr rxr xcd xci xcr xcx xdc xde xdi xdk xdr xed xee xer xex xic xie xii xix xke xrc xrd xrx xxi xxx