a-a a-b a-i aaa aab aae aai aan aao aas ab- aba abb abe abi abn abo abs aea aeb aee aei aen aeo aes ai- aia aib aie aii ain aio ais an- ana anb ane ani ann ano ans aoa aob aoe aoi aon aoo aos as- asa asb ase asi asn aso ass baa bab bae bai ban bao bas bba bbb bbe bbi bbn bbo bbs be- bea beb bee bei ben beo bes bi- bia bib bie bii bin bio bis bna bnb bne bni bnn bno bns boa bob boe boi bon boo bos bsa bsb bse bsi bsn bso bss eaa eab eae eai ean eao eas eba ebb ebe ebi ebn ebo ebs eea eeb eee een eeo ees eia eib eie eii ein eio eis en- ena enb ene eni enn eno ens eo- eoa eob eoe eoi eon eoo eos es- esa esb ese esi esn eso ess ia- iaa iab iae iai ian iao ias iba ibb ibe ibi ibn ibo ibs ie- iea iee iei ien ies iia iib iie iii iin iio iis in- ina inb ine ini inn ino ins io- ioa iob ioe ioi ion ioo ios is- isa isb ise isi isn iso iss n-i naa nab nae nai nan nao nas nba nbb nbe nbi nbn nbo nbs ne- nea neb nee nei nen neo nes nia nib nie nii nin nio nis nna nnb nne nni nnn nno nns no- noa nob noe noi non noo nos nsa nsb nse nsi nsn nso nss o-i oaa oab oae oai oan oao oas ob- oba obb obe obi obn obo obs oea oeb oee oei oen oeo oes oia oib oie oii oin oio ois on- ona onb one oni onn ono ons oo- ooa oob ooi oon ooo oos os- osa osb ose osi osn oso oss saa sab sae sai san sao sas sba sbb sbe sbi sbn sbo sbs se- sea seb see sei sen seo ses sia sib sie sii sin sio sis sna snb sne sni snn sno sns soa sob soe soi son soo sos ss- ssa ssb sse ssi ssn sso sss