parens aprens praens rpaens arpens rapens paerns aperns pearns eparns aeprns eaprns preans rpeans perans eprans repans erpans arepns raepns aerpns earpns reapns erapns parnes aprnes pranes rpanes arpnes rapnes panres apnres pnares npares anpres napres prnaes rpnaes pnraes npraes rnpaes nrpaes arnpes ranpes anrpes narpes rnapes nrapes paenrs apenrs peanrs epanrs aepnrs eapnrs paners apners pnaers npaers anpers napers penars epnars pnears npears enpars nepars aenprs eanprs aneprs naeprs enaprs neaprs prenas rpenas pernas eprnas repnas erpnas prneas rpneas pnreas npreas rnpeas nrpeas penras epnras pneras nperas enpras nepras renpas ernpas rnepas nrepas enrpas nerpas arenps raenps aernps earnps reanps eranps arneps raneps anreps nareps rnaeps nraeps aenrps eanrps anerps naerps enarps nearps renaps ernaps rneaps nreaps enraps neraps paresn apresn praesn rpaesn arpesn rapesn paersn apersn pearsn eparsn aeprsn eaprsn preasn rpeasn perasn eprasn repasn erpasn arepsn raepsn aerpsn earpsn reapsn erapsn parsen aprsen prasen rpasen arpsen rapsen pasren apsren psaren sparen aspren sapren prsaen rpsaen psraen spraen rspaen srpaen arspen raspen asrpen sarpen rsapen srapen paesrn apesrn peasrn epasrn aepsrn eapsrn pasern apsern psaern spaern aspern sapern pesarn epsarn psearn spearn esparn separn aesprn easprn aseprn saeprn esaprn seaprn presan rpesan persan eprsan repsan erpsan prsean rpsean psrean sprean rspean srpean pesran epsran pseran speran espran sepran respan erspan rsepan srepan esrpan serpan arespn raespn aerspn earspn reaspn eraspn arsepn rasepn asrepn sarepn rsaepn sraepn aesrpn easrpn aserpn saerpn esarpn searpn resapn ersapn rseapn sreapn esrapn serapn parnse aprnse pranse rpanse arpnse rapnse panrse apnrse pnarse nparse anprse naprse prnase rpnase pnrase nprase rnpase nrpase arnpse ranpse anrpse narpse rnapse nrapse parsne aprsne prasne rpasne arpsne rapsne pasrne apsrne psarne sparne asprne saprne prsane rpsane psrane sprane rspane srpane arspne raspne asrpne sarpne rsapne srapne pansre apnsre pnasre npasre anpsre napsre pasnre apsnre psanre spanre aspnre sapnre pnsare npsare psnare spnare nspare snpare anspre naspre asnpre sanpre nsapre snapre prnsae rpnsae pnrsae nprsae rnpsae nrpsae prsnae rpsnae psrnae sprnae rspnae srpnae pnsrae npsrae psnrae spnrae nsprae snprae rnspae nrspae rsnpae srnpae nsrpae snrpae arnspe ranspe anrspe narspe rnaspe nraspe arsnpe rasnpe asrnpe sarnpe rsanpe sranpe ansrpe nasrpe asnrpe sanrpe nsarpe snarpe rnsape nrsape rsnape srnape nsrape snrape paensr apensr peansr epansr aepnsr eapnsr panesr apnesr pnaesr npaesr anpesr napesr penasr epnasr pneasr npeasr enpasr nepasr aenpsr eanpsr anepsr naepsr enapsr neapsr paesnr apesnr peasnr epasnr aepsnr eapsnr pasenr apsenr psaenr spaenr aspenr sapenr pesanr epsanr pseanr speanr espanr sepanr aespnr easpnr asepnr saepnr esapnr seapnr panser apnser pnaser npaser anpser napser pasner apsner psaner spaner aspner sapner pnsaer npsaer psnaer spnaer nspaer snpaer ansper nasper asnper sanper nsaper snaper pensar epnsar pnesar npesar enpsar nepsar pesnar epsnar psenar spenar espnar sepnar pnsear npsear psnear spnear nspear snpear enspar nespar esnpar senpar nsepar snepar aenspr eanspr anespr naespr enaspr neaspr aesnpr easnpr asenpr saenpr esanpr seanpr ansepr nasepr asnepr sanepr nsaepr snaepr ensapr nesapr esnapr senapr nseapr sneapr prensa rpensa pernsa eprnsa repnsa erpnsa prnesa rpnesa pnresa npresa rnpesa nrpesa penrsa epnrsa pnersa npersa enprsa neprsa renpsa ernpsa rnepsa nrepsa enrpsa nerpsa presna rpesna persna eprsna repsna erpsna prsena rpsena psrena sprena rspena srpena pesrna epsrna pserna sperna esprna seprna respna erspna rsepna srepna esrpna serpna prnsea rpnsea pnrsea nprsea rnpsea nrpsea prsnea rpsnea psrnea sprnea rspnea srpnea pnsrea npsrea psnrea spnrea nsprea snprea rnspea nrspea rsnpea srnpea nsrpea snrpea pensra epnsra pnesra npesra enpsra nepsra pesnra epsnra psenra spenra espnra sepnra pnsera npsera psnera spnera nspera snpera enspra nespra esnpra senpra nsepra snepra renspa ernspa rnespa nrespa enrspa nerspa resnpa ersnpa rsenpa srenpa esrnpa sernpa rnsepa nrsepa rsnepa srnepa nsrepa snrepa ensrpa nesrpa esnrpa senrpa nserpa snerpa arensp raensp aernsp earnsp reansp eransp arnesp ranesp anresp naresp rnaesp nraesp aenrsp eanrsp anersp naersp enarsp nearsp renasp ernasp rneasp nreasp enrasp nerasp aresnp raesnp aersnp earsnp reasnp erasnp arsenp rasenp asrenp sarenp rsaenp sraenp aesrnp easrnp asernp saernp esarnp searnp resanp ersanp rseanp sreanp esranp seranp arnsep ransep anrsep narsep rnasep nrasep arsnep rasnep asrnep sarnep rsanep sranep ansrep nasrep asnrep sanrep nsarep snarep rnsaep nrsaep rsnaep srnaep nsraep snraep aensrp eansrp anesrp naesrp enasrp neasrp aesnrp easnrp asenrp saenrp esanrp seanrp anserp naserp asnerp sanerp nsaerp snaerp ensarp nesarp esnarp senarp nsearp snearp rensap ernsap rnesap nresap enrsap nersap resnap ersnap rsenap srenap esrnap sernap rnseap nrseap rsneap srneap nsreap snreap ensrap nesrap esnrap senrap nserap snerap
Note: these 'words' (valid or invalid) are all the permutations of the word parens. These words are obtained by scrambling the letters in parens.