c-- ccc ccd cce ccn cct ccx cdc cdd cde cdn cdt cdx ce- cec ced cee cen cet cex cn- cnc cnd cne cnn cnt cnx ctc ctd cte ctn ctt ctx cxc cxt cxx dcc dcd dce dcn dct dcx ddc ddd dde ddn ddt ddx de- dec ded dee den det dex dnc dnd dne dnn dnt dtc dtd dte dtn dtt dtx dxc dxd dxn dxt dxx ec- ecc ecd ece ecn ect ecx ed- edc edd ede edn edt edx eec eed eee een eet eex en- enc end ene enn ent etc etd ete etn ett etx ex- exc exd exe ext exx ncc ncd nce ncn nct ncx ndc ndd nde ndn ndt ne- nec ned nee nen net nex nnc nne nnn nnt ntc ntd nte ntn ntt ntx nxc nxd nxt t-x tcc tcd tce tcn tct tcx tdc tdd tde tdn tdt tdx te- tec ted tee ten tet tex tnc tnd tne tnn tnt tnx ttc ttd tte ttn ttt ttx txe txn txt xcd xcx xdc xde xdt xed xee xen xet xex xnc xtc xtx xxx