ndrin dnrin nrdin rndin drnin rdnin ndirn dnirn nidrn indrn dinrn idnrn nridn rnidn nirdn inrdn rindn irndn drinn rdinn dirnn idrnn ridnn irdnn ndrni dnrni nrdni rndni drnni rdnni ndnri dnnri nndri nndri dnnri ndnri nrndi rnndi nnrdi nnrdi rnndi nrndi drnni rdnni dnrni ndrni rndni nrdni ndinr dninr nidnr indnr dinnr idnnr ndnir dnnir nndir nndir dnnir ndnir nindr inndr nnidr nnidr inndr nindr dinnr idnnr dninr ndinr indnr nidnr nrind rnind nirnd inrnd rinnd irnnd nrnid rnnid nnrid nnrid rnnid nrnid ninrd innrd nnird nnird innrd ninrd rinnd irnnd rnind nrind inrnd nirnd drinn rdinn dirnn idrnn ridnn irdnn drnin rdnin dnrin ndrin rndin nrdin dinrn idnrn dnirn ndirn indrn nidrn rindn irndn rnidn nridn inrdn nirdn
Note: these 'words' (valid or invalid) are all the permutations of the word ndrin. These words are obtained by scrambling the letters in ndrin.