A strongly complete proof system for propositional dynamic logic ...

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Gerard Renardel de Lavalette, Barteld Kooi*. Rineke Verbrugge†. Abstract. Propositional dynamic logic (PDL) is complete but not compact. As a consequence ...
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 gne guukijgpilf l{ pqs ifoxjpilf qeulpqsniny    lr pqsvs in g  ripq › )     gfo › )  )    Ÿ y ' ipq pqs ifoxjpilf qeulpqsnin‰ rs msp › )       gfo › )   )      Ÿ ‰ nl ripq & rs lwpgif › )      Ÿ y !  š i{ › ) Ÿ   ‰ pqsf €we &   6 „ › ) Ÿ  Ÿ   Ÿ  / ripq &  rs vshlts

pqs pgxplklme Ÿ  Ÿ gfo lwpgif ›   Ÿ  y   š ifoxjpilf ltsv g osvitgpilf l{ ›   Ÿ y   gne‰ ripq 45 y

zgŒs ‚ gfo guuke ‚ 4 prijsy  ! ' s qgts  } / ! / .   Ÿ œ   } / ! / . ! Ÿ / tig  gfo  & rs lwpgif }   }! / .   Ÿ œ   } }! / . !  Ÿ   gne‰ tig  gfo & y   zqsns jgnsn {lkklr oivsjpke we pqs ifoxjpilf qeulpqsniny  f ihhsoigps jlfns¤xsfjs l{ ‚ 46 in pqgp i{ › ) Ÿ in ‚ƒ7  ifjlfninpsfp‰ pqsf ›   , Ÿ y     b \_\cb  _`   _^ ‹f pqin nsjpilf‰ rs jlfniosv g Šˆso kgfmxgms   y ' s nqgkk uvlts npvlfm jlhukspsfsnn l{ ‚ƒ7 tig pqs sfŒif jlfnpvxjpilf l{ g jgflfijgk hlosk if nsjpilf  y~y zqsvs gvs prl npsunš Švnp rs nqlr pqgp stsve ‚ƒ7  jlfninpsfp nsp jgf ws sˆpsfoso pl g hgˆihgk ‚ƒ7  jlfninpsfp nsp‰ pqsf rs jlfnpvxjp g viuŒs hlosk jlfninpifm l{ hgˆihgk ‚ƒ7  jlfninpsfp nspny ‹f nsjpilf  y‡ rs nqlr pqgp pqin hlosk olsn flp ngpin{e uvlmvgh qgvhlfe‰ we mitifm g jlxfpsvhlosky     7

' s vsjgkk pqs lwtilxn {gjp pqgp g jlkksjpilf l{ {lvhxkgs › in hgˆihgk ‚ƒ7  jlfninpsfp i ip in ‚ƒ7  jlfninpsfp €iysy ›  = + „ gfo › jlfpgifn sˆgjpke lfs

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¦ ›y zl nqlr pqgp }! / . ! Ÿ ›‰ gnnxhs xnifm jlfpvgulnipilf pqgp pqin in flp pqs jgnsš pqsf we € „‰ , }! / . ! Ÿ ›y + sp ws pqs ifosˆ ripq Ÿ   }! / . ! Ÿ ‰ pqsf ›   = Ÿ  €{lv lpqsvrins‰ we pqs Švnp jgns if pqs osŠfipilf l{ ›   ‰ }! / . ! Ÿ ›  ¦ ›„‰ nl , }! / .  Ÿ ›  ¦ › {lv nlhs  we pqs kgnp jgns l{ pqs osŠfipilf l{ ›   y xp gknl‰ we gnnxhupilf‰ }! / .  Ÿ ›‰ nl  , }! / .  Ÿ ) }! / .  Ÿ › {lv nlhs   ‰ jlfpvgoijpifm pqs jlfninpsfje l{ › €~„y < 45 š we €‡„y < % š oivsjp jlfns¤xsfjs l{ pqs ifoxjpilf qeulpqsniny < & š nl ›¥   ›¥¥ gfo ›¥ - ›¥¥   Ÿ {lv nlhs ›¥¥y e pqs ifoxjpilf qeulpqsnin‰ rs msp ›¥¥ ¦ ›‰ nl ›¥ - ›¥¥ ¦ › / we guukeifm pqs ifoxjpilf qeulpqsnin gmgif rs lwpgif Ÿ ›y  lr rs jgf osŠfs pqs jgflfijgk hlosk fssoso {lv npvlfm jlhukspsfsnny

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‹p in stiosfp € „ {lkklrn {vlh }  ›y zl nss pqgp € „ ihukisn }  › gn rskk‰ rs gvmxs tig jlfpvgulnipilfy †l gnnxhs }  = ›‰ iysy €we hgˆ  ihgk jlfninpsfje„ , }  ›y ' s nqgkk nqlr pqgp pqsvs in g hgˆihgk jlfninpsfp  ripq  {lv gkk nxjq pqgp }!  ›‰ gfo ,  y e pqs + ifosfwgxh kshhg‰ ip nx  jsn pl nqlr pqgp  œ }   › -  , in jlfninpsfpy  nnxhs ip in flp‰ iysy  œ }   › -  ,   + ‰ pqsf  œ }   ›   tig ‚ 46 y zqxn‰ ripq  45 š  }   œ }   ›   }  y sfjs   “’‘ “’  ›   }  gfo }  ›‰ jlfpvgoijpifm pqs gnnxhupilf }  = ›y ‡y !  . !š 7 ) › œ }. ! {lv gkk 7 ) › œ }.   €}.   › {lv gkk „ }. ! ›‰ xnifm pqs ifoxjpilf qeulpqsnin if pqs nsjlfo npsu‰ gfo  ‰  ! if pqs kgnp npsuy  lps pqgp if pqs pvxpq kshhg‰ rs ol flp uvlts pqs oxgk uvlusvpe {lv uvlmvghn › 9 D  i Ÿ  {lv gkk Ÿ nxjq pqgp }!  Ÿ › €ip qlkon we osŠfi pilf {lv gplhij uvlmvghn  „y ‹f nsjpilf  y‡ rs skgwlvgps lf pqin kgjŒ l{ {xkk qgvhlfe y   15    1 65 2  44  ! "7   & ‘ ˜ !& ‘  &  –   “  ––  ’   &  ’   &   “’ ‘  & –  ”• 1 • &   A  & ”  “’  ––  “’ 1 – & Ÿ  ” 0  ––  & ‘ “  “’ 1 – &  $  œ ž Ÿ   – &    Ÿ A  1  e jlfpvgulnipilfy †xuulns   = Ÿ ‰ pqsf  -  , Ÿ in jlfninpsfpy e kshhg ‡‰  -  , Ÿ in sˆpsfoso pl g hgˆihgk jlfninpsfp nsp › ripq , Ÿ ›y  lr we kshhg  ‰ rs jlfjkxos pqgp if pqs jgflfijgk viuŒs hlosk‰ 7 ) › œ= Ÿ ‰ gn osnivsoy  lps pqgp pqs jlhukspsfsnn uvll{ ihhsoigpske mitsn g jgflfijgk npgfogvo hlosk‰ jlfpvgve pl pqs sgvke uvll{n l{ rsgŒ jlhukspsfsnn {lv ‚ƒ gn pqse guusgv if }‰ * ‰ rqijq xns flfnpgfogvo hloskny









       

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~š  uijpxvs l{ pqs jlxfpsvhlosk 7 y zqs nlkio kifsn ifoijgps pqs gjjsnniwikipe vskgpilf l{ pqs gplhij uvlmvgh  ‰ pqs ognqso kifsn {lv y Ÿ ‰ rqsvs % ) gvs prl rlvkon if nlhs hlosk 7 pl ws jlfnpvxjpsoy lvs uvsjinske‰ rs nqgkk nqlr  Ÿ €7 ) œ } !  Ÿ 7 ) % œ Ÿ „ € „   Ÿ €7 ) œ }   Ÿ 7 ) % œ , Ÿ „ €2 „     lr € „ ihhsoigpske ihukisn  Ÿ œ } ! Ÿ › ¦  ‰ gfo €2 „ ihukisn ”“‘ › 9  §  ‰ rqsvs 9  §  €9  „! in mitsf we pqs jgflfijgk hlosk €nss osŠfipilf * „y ' s osŠfs 7 if prl npsunš Švnp rs npxoe pqs hlosk    )   ‰ pqsf rs sˆpsfo  pl 7 y ‹f  ‰ rs npgvp ripq ifpsvuvspifm lfke pqs kgfmxgms   : €fl uvlulnipilfgk gplhn wsniosn + ‰ gfo  gn pqs lfke gplhij uvlmvgh„ / rqsf mlifm pl 7 ‰ rs goo pqs gplhij uvlmvgh y zqs sˆpsfnilf l{ 9: in pqs npvijp lvosv vskgpilf  lf y ' s rvips } Ÿ  {lv  œ  ) œ Ÿ ‰ gfo } !  {lv 9 D ¦ y †ss ) imxvs ~y ' s nge pqgp ¦ in ’ & ’&  & ”‘  ! – & i  } Ÿ  {lv nlhs Ÿ y zqs jvxjigk uvlusvpe l{  in {lv stsve Ÿ if   : ) } Ÿ  in Šfips lv jlŠfips €* „ € ¦ in jlŠfips i in Šfips„y †l pqsvs in fl {lvhxkg Ÿ ripq symy } Ÿ    ‡ œ y zqs qgvo ugvp if uvltifm €* „ kisn if Šfoifm pqs jlvvsnulfoifm uvlusvpe {lv uvlmvghnš rqijq vskgpilfn lf gvs vsuvsnsfpgwks gn } !  ‰ {lv nlhs uvlmvgh ! if   : . ' s nqgkk osŠfs pqin uvlusvpe xnifm   € „‰ pqs jlkksjpilf l{  ‘  ! – & nxwnspn l{ š   € „ i  € } ) % „ ¦ „



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‹p in vgpqsv lwtilxn pqgp   € „ in jklnso xfosv - gfo  y lvs nxvuvinifm in pqgp   € „ in jklnso xfosv ”' ”  ‘ & jlf…xfjpilfny zqin in g jlfns¤xsfjs l{ pqs {gjp pqgp €npvijp ifjkxnilf„ in g rskklvosvifm lf   € „‰ qsfjs stsve ifŠfips jlf…xfjpilf "  " l{  npgwks nspn in s¤xgk pl nlhs Šfips nxwjlf…xfjpilf "  - ¢ ¢ ¢ - " y ' s sˆpsfo npgwikipe pl vskgpilfnš    € „ in osŠfso we 9    € „ i   € 9       $    œ  9    € „„ gfo jkgih š    € „ in jklnso xfosv Šfips jlf…xfjpilfn gfo gvwipvgve oin…xfj  pilfn‰ gfo xfosv G €jlhulnipilf„y  lr rs jgf jqgvgjpsvins pqs vsuvsnsfpgwks vskgpilfnš 9  } !  {lv nlhs uvlmvgh ! if   : i 9  9  - 9 - 9  rqsvs‰ {lv nlhs ‰ 9   > lv 9    € ) „ œ ‰ 9  > lv 9   € )  „ œ   )     {lv nlhs  ‰ gfo 9     € „y zqs lfke i{ , ugvp in uvltso plmspqsv ripq €* „ if nihxkpgfslxn ifoxjpilf ltsv Ÿ gfo ! y ' s sˆpsfo  pl 7   # ) 9 : ) 9  ‰ rqsvs #  - % ) -   )   œ  $   9 :   € )  „ œ   -  €% ) „ œ 9    € )  „ -  € )  ) ~  „ ) €  )  ) „ œ 

-  €  )   )  )  ~  „ œ )  )  $  $ †ss ) imxvs ~y £wnsvts pqgp 9 :    € )  „ œ   ‰ pqs sˆpsfnilf l{ 9 : if  y ' s jkgih š {lv gkk Ÿ if   : 7 ) % œ Ÿ i } Ÿ  in jlŠfipsy € „ €vsjgkk pqgp }  osflpsn ifpsvuvspgpilf if  / rs nqgkk xns 9 D pl osflps pqs ifpsvuvspgpilf l{ ! if 7 „y zqin in uvltso tig nihxkpgfslxn ifoxjpilf ltsv Ÿ gfo ! if   : ‰ plmspqsv ripq pqs npgpshsfpn €% ) „ 9 D  œ € ) „ } !  jlŠfips‰ gfo €% ) % „ 9 D  € ) „ œ € ) „ } !  jlŠfipsy  knl‰ {lv gkk š 7 ) œ Ÿ 7 ) œ Ÿ   ) œ Ÿ  €( „ rqsvs Ÿ  in osŠfso gn Ÿ ripq gkk ljjxvvsfjsn l{ vsukgjso we + . y zqs Švnp s¤xitgksfjs if €( „ gknl qlkon {lv  % y  n g jlfns¤xsfjs l{ € „ gfo €( „‰ rs qgts‰ {lv gkk Ÿ if   : 7 ) % œ Ÿ    €7 )  œ Ÿ „ gfo pqin sfpgikn €„š {lv i{ 7 ) œ } ! Ÿ ‰ pqsf 7 ) œ Ÿ {lv stsve ‰ qsfjs 7 ) œ Ÿ {lv stsve ‰ nl 7 ) % œ Ÿ gfo 7 ) % œ Ÿ y ‹f lvosv pl tsvi{e €2 „‰ rs uxp Ÿ   }   + š pqsf  €7 ) œ Ÿ   ) œ Ÿ  „ gfo  )  €  )   # 7 )  )   œ Ÿ „‰ nl ifosso 7 ) œ }   Ÿ gfo 7 ) % œ , Ÿ €xnifm € „„y zqsvs{lvs wlpq € „ gfo €2 „  qlko‰ gfo uvlmvgh oinqgvhlfe in oshlfnpvgpsoy 





















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Œflrksoms   : Ÿ  : : Ÿ ulnipits ifpvlnusjpilf   ,: Ÿ  : ,: Ÿ fsmgpits ifpvlnusjpilf ' s sˆpsfo gkk {lxv gˆilh nenpshn pl ifŠfipgve uvll{ nenpshn   &   7 ‰   &   7 ‰    &   7 ‰ gfo   &   7 we gooifm g Šˆso nsp l{ osvitgpilf vxksny ' s Švnp ifpvloxjs nlhs flpgpilf if lvosv pl osnjviws pqs ifŠfipgve ifpvl  oxjpilf vxks {lv y ' s rgfp pqin vxks pl jlfpgif gkk ifnpgfjsn l{ pqs {lvh  Ÿ   : €Ÿ    €¢ ¢ ¢   „„ œ ) ~   Ÿ   : €Ÿ    €¢ ¢ ¢  „„ ) rqsvs  in pqs lwtilxn gwwvstigpilf osŠfso ifoxjpitske we  gfo     y zqs fsgp rge pl {lvhxkgps pqs ifŠfipgve vxks in pl ifpvloxjs Šfips ns¤xsfjsn   €  ) ¢ ¢ ¢ )   „ rqsvs pqs  gvs sipqsv {lvhxkgs lv hlogkipisn : {lv   ‰ ripq €„ Ÿ  Ÿ € /  „Ÿ   € „ Ÿ / €:  „ Ÿ  : €€ „ Ÿ „ zqs ifŠfipgve vxks hge pqsf ws {lvhxkgpso gn  € „  Ÿ œ ) ~   € „ Ÿ y ' s mits pqs osvitgpilf vxksn {lv pqs ifŠfipgve nenpshny

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  Ÿ i{ Ÿ in gf gˆilh l{  €hloxn ulfsfn„ Ÿ ) Ÿ     € „  Ÿ œ ) ~   € „ Ÿ €ifŠfipgve  ifpvloxjpilf„ 45 i{   Ÿ pqsf   : Ÿ €fsjsnnipgpilf„ % i{ ›   Ÿ pqsf › )    Ÿ €rsgŒsfifm„ &  i{ ›    gfo › )    Ÿ pqsf ›   Ÿ  lr pqs vsgosv hge jqsjŒ pqgp {lv pqsns nenpshn‰ pqs osvitso vxksn  & ‰ ‚ 4 ‰ &  6 ‰ gfo ‚ 46 l{ kshhg ~ jgf ws uvltso‰ gn rskk gn pqs {lkklrifm gfg  klmxs l{ npvlfm fsjsnnipgpilf  45 š  45 i{ ›   Ÿ pqsf : ›   : Ÿ €npvlfm fsjsnnipgpilf {lv Œflrksoms„ ‹p in ihhsoigps pqgp gkk {lxv nenpshn gvs nlxfo ripq vsnusjp pl pqs guuvl  uvigps nshgfpijnš   &   7 {lv gkk viuŒs {vghsn‰   &   7 {lv vs I sˆits lfsn‰    &   7 {lv vs I sˆits pvgfnipits lfsn‰ gfo   &   7 {lv s¤xitgksfjs vskg  pilfny   15 /  & ‘  !&  ”— “ ‘  & —‘ &     &   7 $   &   7 $    &   7 $  ” 0   &   7 A  & ”   ‘’“”•–— “   – & ‘ & &  ‘ ’ && ‘ ‘“ ‘ &  ’“ ’   ‘ &  & ‘ “  ’  & A  1  436  e g sfŒif jlfnpvxjpilf l{ g jgflfijgk hlosk‰ gfgklmlxnke gn if nsjpilf  y~y zqs uvsnsfjs l{ pqs guuvluvigps gˆilhn {vlh   ‰   ‰ gfo   if pqs hgˆihgk jlfninpsfp nspn ifoxjsn pqs guuvluvigps uvlusvpisn l{ pqs gjjsnniwikipe vskgpilfn if pqs jgflfijgk hlosky ‹f pqs gfgklmxs l{ pqs + ifosfwgxh kshhg‰ pqs kgnp jkgxns {lv ›   nqlxko ws ›    ›  -  , Ÿ  ) , € „ lpqsvrins‰ rqsvs  in pqs ksgnp fgpxvgk fxhwsv ~ nxjq pqgp ›  = € „ €gfo Ÿ in l{ pqs {lvh € „ „ y zqs osŠfipilf l{ pqs jgflfijgk hlosk in gn xnxgk {lv suinpshij klmijny zqs hgif oi svsfjs {vlh pqs uvll{ l{ pqs zvxpq kshhg  in pqs ifoxjpilf npsu {lv lusvgplv ‰ rqijq rlvŒn tsve nhllpqkeš 7 ) › œ {lv gkk ) ~ 7 ) › œ

 €  › {lv gkk ) ~„ ›‰ xnifm pqs ifoxjpilf qeulpqsnin if pqs nsjlfo npsu‰ gfo #  ‰ & if pqs kgnp npsuy ‹p in jksgv {vlh pqs uvll{ nŒspjq pqgp gkk {lxv suinpshij klmijn ripq jlh  hlf Œflrksoms gvs jgflfijgkš lf pqsiv jgflfijgk {vghsn‰ gkk pqsiv gˆilhn gvs tgkio }~y  5 2   zl nqlr pqgp pqs ifŠfipgve uvll{ nenpshn gvs npvlfmsv pqgf pqs xnxgk rsgŒke jlhuksps lfsn‰ ksp xn kllŒ gp pqs rskk Œflrf sˆghuks l{ pqs eŽgfpifs msfsvgkny  lfniosv g nipxgpilf l{ prl gvhe vsmihsfpn lf prl qikkn lf wlpq niosn l{ g tgkkse‰ if rqijq g qlnpiks gvhe in nipxgpsoy ‹{ pqs prl vsmihsfpn gppgjŒ nihxkpgfslxnke‰ pqse rikk jlf¤xsv pqs sfshey ‹{ lfke lfs l{ pqs vsmihsfpn gppgjŒn‰ ip rikk ws os{sgpso we pqs sfshey zqsvs in fl  # &













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ifipigk wgppks ukgf gtgikgwks rqijq pqs prl vsmihsfpn gmvss xulfy  sipqsv msfsvgk l{ pqs vsmihsfpn rlxko osjios pl gppgjŒ ripqlxp Œflrifm {lv nxvs pqgp pqs lpqsv lfs rikk gknl gppgjŒ €{vlh }3 „y zqs jlhhgfoifm msfsvgk l{ pqs Švnp oitinilf rinqsn pl jllvoifgps g nihxkpgfslxn gppgjŒ €gp nlhs pihs pqs fsˆp oge„y zqs msfsvgkn jgf jlhhxfijgps lfke we hsgfn l{ hsnnsfmsvny  lvhgkke‰ ip pgŒsn g hsnnsfmsv lfs qlxv pl msp {vlh lfs sfjghuhsfp pl pqs lpqsvy lrstsv‰ ip in ulnniwks pqgp qs rikk msp klnp if pqs ogvŒ‰ lv rlvns esp‰ ws jgupxvso we pqs sfshey )lvpxfgpske‰ lf pqin ugvpijxkgv fimqp‰ stsvepqifm mlsn nhllpqkey lr klfm rikk ip pgŒs pqsh pl jllvoifgps gf gppgjŒ . €{vlh }‡„y f{lvpxfgpske‰ ip pxvfn lxp pqgp flvhgkke‰ jlhhlf Œflrksoms ghlfm pqs prl msfsvgkn jgfflp ws vsgjqso if pqin rgeš gp sgjq ulifp if pihs‰ lfke

 Ÿ {lv nlhs ) ~ in gjqistso‰ rqsvs Ÿ in gp ksgnp lfs hsnngms rgn oskitsvso y €†ss }‡‰ ~  {lv sˆukgfgpilfn l{ pqin gfo nihikgv uqsflhsfg„y ' s qgts g nxmmsnpilf {lv pqs xf{lvpxfgps msfsvgkny ‹p {lkklrn ihhsoi gpske we & pqgp   Ÿ œ ) ~   Ÿ {lv gfe l{ pqs {lxv ifŠfipgve suinpshij uvll{ nenpshn  €xfkiŒs {lv pqs xnxgk Šfipgve uvll{ nenpshn„y  lr pqs msfsvgkn lfke fsso pl qivs g hsnnsfmsv rql vxfn prijs gn {gnp lf stsve fsr vlxfo gn lf pqs uvstilxn lfs / pqs Švnp vlxfo pgŒsn ‡ qlxvn‰ pqs nsjlfo vlxfo ~ qlxv‰ gfo nl lf‰ go ifŠfipxh y †xhhifm pqs nsvisn‰ g{psv 2 qlxvn gkk pqs   Ÿ œ ) ~ gvs gjqistso‰ rqsvswe Ÿ qlkony ' s gohip pqgp pqs nxmmsnpilf jgfflp ws hloskso gn g hxkpi gmsfp nenpsh gjjlvoifm pl }‡ wsjgxns pqs pihs npsun gvs flp npvxjpxvso gn pqs fgpxvgk fxhwsvn % wxp gn % ~y lvsltsv‰ nlhs uvgjpijgk uvlwkshn npikk fsso pl ws nlktso‰ rqijq rs ksgts pl uqenijinpny  _\b a  c_\

‹f pqin ugusv rs qgts uvsnsfpso g uvll{ nenpsh {lv uvlulnipilfgk oefghij klmij rqijq in npvlfmke jlhukspsy ‹p jgf gknl ws guukiso pl suinpshij klmij ripq jlhhlf Œflrksomsy ' s nxnusjp pqgp pqs vsgnlf pqgp pqs jgflfijgk hlosk hspqlo rlvŒn {lv pqin gˆilhgpingpilf‰ in pqgp pqs ifŠfipgve !  ifpvloxjpilf vxks in hxjq jklnsv pl pqs nshgfpijn pqgf pqs xnxgk ifoxjpilf gˆilh lv vxksy zqs kgppsv kifŒn xu ripq pqs iosg l{ pqs kssfs npgv gn g Šˆso ulifp‰ rqsvsgn lxv vxks kifŒn xu ripq pqs iosg pqgp ip in gf ifŠfipgve jlf…xfjpilfy lrstsv‰ gn rs nqlrso if nsjpilf  y‡‰ pqsvs in fl jlhuksps qgvhlfe wsprssf pqs uvll{ nenpsh gfo pqs nshgfpijny zqs jlxfpsvhlosk xnso if pqs jlhukspsfsnn uvll{ qgn  “’ 1 –    ’  “”—y zqin in nqlrf if pqs pvxpq kshhgy  ’“•’    ’  “”— in xfgppgifgwksy zl lxv nxvuvins ip rgn flp fssoso {lv pqs jlhukspsfsnn uvll{y zl lxv gnplfinqhsfp ip rgn flp stsf pvxsy  kpqlxmq rs jghs xu ripq g jlxfpsvhlosk vgpqsv ¤xijŒke‰ pqs nxwpkspe l{ pqs gvmxhsfpn iftlktso‰ rgn gknl xfsˆusjpsoy ‹p rlxko ws ifpsvsnpifm pl pve pl jlfnpvxjp g {xkke qgvhlfilxn hlosk {lv ‚ƒ7 y  n l{ esp rs oio flp Šfo lfs if pqs kipsvgpxvsy ~*

zqsvs npikk vshgif nlhs innxsn pqgp fsso pl ws iftsnpimgpso {xvpqsvy |vlulnipilfgk oefghij klmij gfo suinpshij klmij ripq jlhhlf Œflrksoms gvs sˆghuksn rqsvs pqs ifpvloxjpilf l{ gf ifŠfipgve vxks jgf ws xnso pl gp  pgif npvlfm jlhukspsfsnn‰ gkpqlxmq pqs klmijn gvs flp nshgfpijgkke jlhugjpy ‹p nqlxko ws iftsnpimgpso qlr pl jqgvgjpsvins pqs jkgnn l{ flf  jlhugjp klmijn rqsvs pqs ifpvloxjpilf l{ nxjq gf ifŠfipgve vxks jgf gknl ksgo pl g npvlfm jlhukspsfsnn vsnxkpy zqs msfsvgk guuvlgjq l{ - lkowkgpp }2  nsshn pl ws g mllo npgvpifm ulifpy  flpqsv ifpsvsnpifm innxs in rqspqsv pqs vskgpilf ›   Ÿ wsprssf vsjxv  nitske sfxhsvgwks nspn l{ {lvhxkgs › gfo {lvhxkgs Ÿ in osjiogwksy b  \_   `    \]  ' s pqgfŒ ' ih snnskifŒ {lv pqs oinjxnnilf lf oinqgvhlfe gfo prl gflfe  hlxn vs{svssn {lv pqsiv jlhhsfpn lf gf sgvkisv tsvnilf l{ pqin ugusvy

  ^  \b  }~ |y kgjŒwxvf‰ y os  i…Œs‰ gfo  y sfshgy  “0  –  “•  ‰ tlkxhs * l{    !’ 0• & ’  ‘ ”  &“’&‘ –  “   1 ‘ &’   &” &y  ghwvioms fi tsvnipe |vsnn‰  ghwvioms‰ ‡  ~y }‡  y )gmif‰  y  y gkusvf‰  y lnsn‰ gfo y  y gvoiy & “”  ”•  !“ 1 ‘  ”“ & – &0• & y ‹z |vsnn‰  ghwvioms‰ gnngjqxnsppn‰ ~ 33* y }   y - lkowkgppy  “•  “  &  ” 0  “   1 ‘  ‘ “”‰ tlkxhs ( l{     & ‘ 1 ’& “‘ &y  † + ‹‰ †pgf{lvo‰  gki{lvfig‰ ~33 ‡y †sjlfo soipilf‰ vstinso gfo sˆugfosoy }2   y - lkowkgppy   ‘ &  ‘ “  “0  – ‘—‰ tlkxhs 2 l{     & ‘1 ’&

“‘ &y  † + ‹ |xwkijgpilfn‰ †pgf{lvo‰  gki{lvfig‰ ~33 y }*  dy gvsk‰ dy lŽsf‰ gfo  y zixvefy —”    “•  y )lxfogpilf l{  lhuxpifmy ‹z |vsnn‰  ghwvimos‰ gnngjqxnnsppn‰ ‡  y }  |y y ' y fi…fsfwxvmy £f gˆilhgpingpilfn {lv uvlulnipilfgk klmijn l{ uvlmvgh y zsjqfijgk vsulvp‰ fitsvnipe l{ pvsjqp‰ flt ~3 y    †   2 y }( |y y ' y fi…fsfwxvm gfo  y tgf + ssxrsfy £f hloskn {lv uvlulnipilfgk oefghij klmijy  &“’& ‘ – “   1 ‘ & ’   &” &‰ 3 ~š~~ ‡  ‰ ~33 ~y } dy lŽsf gfo  y |gviŒqy  f skshsfpgve uvll{ l{ pqs jlhukspsfsnn l{ |d + y  &“’& ‘ –  “   1 ‘ & ’   & ” & ‰ ~2 š~~ ~~‰ ~3 ~y ~

}3   y  y  qy sesv gfo ' y tgf osv lsŒy "  ‘ &   “•   “’    ” 0  “   1 ‘ &’   &” &y  ghwvioms fitsvnipe |vsnn‰  ghwvioms‰ ~33* y }~  - y ivŒlrnŒgy |+ uvlulnipilfgk gkmlvipqhij klmijy ‹f  y  fmsksv‰ soiplv‰  “•  “  ’“•’  ‰ tlkxhs ~‡ * l{  & ‘1 ’& “‘ &  ”  “   1 ‘ &’   &” &‰ ugmsn ‡  ~ ~y †uvifmsv svkgm‰ svkif sioskwsvm  sr lvŒ‰ ~3 ~y }~~  y  y |vgppy †shgfpijgk jlfniosvgpilfn lf ) kleo  lgvs klmijy ‹f  ’“ &&0 ”• “ ‘ & ‘  """  —   “ 1 “” ‘ & ( “ 1 ” 0  ‘  “” “  “   1 ‘ & ’   &” &‰ ugmsn ~3 ~‡~‰ ~3( y }~‡ y †smsvwsvmy  jlhukspsfsnn pqslvsh if pqs hlogk klmij l{ uvlmvghny

“‘& “ ‘ &  &’  ”   ‘ &  ‘ –  “ &‘—‰ ‡ 2 € „š ** ‡‰ ~3(( y }~  ) y †pxku gfo  y svwvxmmsy  Œflrksoms  wgnso gkmlvipqh {lv pqs if  psvfsp uvlpljlk z  |y  1 –– & ‘” “ " “”“  & & ’ ‰ *2 špl guusgv‰ ‡  ‡y

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