Starting with polynomial:
P : t^7 - 21*t^5 + 105*t^3 - 105*t
Extension levels are: 7 78
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Trying to find an order 78 Kronrod extension for:
P1 : t^7 - 21*t^5 + 105*t^3 - 105*t
Solvable: 1
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Ending with final polynomial:
P : t^85 - 11866690419886414737173049547543073203951663100451828541154510515452466800952792739822702274396358569/3537904920824957132780746984964619179066754867889052902086708798258542789289048846033859246885922*t^83 + 1382949965987213475072542014394393437729581007924272260942746686929463428493955335299106806311462686834837/258267059220221870692994529902417200071873105355900861852329742272873623618100565760471725022672306*t^81 - 2798737010569838520516292486220274534217321243001275541094010093179804513377595578395295340109253126822807039/516534118440443741385989059804834400143746210711801723704659484545747247236201131520943450045344612*t^79 + 2016724822084125643104727310670177108663422349002945805190089712436669083330522936632400955604820381583643742959/516534118440443741385989059804834400143746210711801723704659484545747247236201131520943450045344612*t^77 - 1102361060970044596973155678374347502270521808312491565019124837778648050026758729269916538187045131165000642056597/516534118440443741385989059804834400143746210711801723704659484545747247236201131520943450045344612*t^75 + 176023560802085483357182183119265056208412266034912886539161599896257149753345411866509905379751700106991586938325/191238103828376061231391728917006442111716479345354210923605880986948258880489126812641040372212*t^73 - 61518981273140104115792941490474742620393629527911571194886893661810570213731527419274934418362866951863936796291425/191238103828376061231391728917006442111716479345354210923605880986948258880489126812641040372212*t^71 + 17756991903346925335466929429210646279467896684908583357133098308215948152845191396685420406843734122806063932339313525/191238103828376061231391728917006442111716479345354210923605880986948258880489126812641040372212*t^69 - 4292894371026895494468930777827170755526959940040641550581681306548468918570561638410752431751368177731490055139242497025/191238103828376061231391728917006442111716479345354210923605880986948258880489126812641040372212*t^67 + 878538891533769599963379284810136542029965366554539964732015313230047985614629952952173851469629748453697031714947592626325/191238103828376061231391728917006442111716479345354210923605880986948258880489126812641040372212*t^65 - 38359421336380591726144359954695267138869933942424259301630700120527641645752166020066200484481900286354576812620445636043875/47809525957094015307847932229251610527929119836338552730901470246737064720122281703160260093053*t^63 + 5753330549880660517676149200794449989370763960764228243779461254353756343068780111371789515960054434322686928350921364821781875/47809525957094015307847932229251610527929119836338552730901470246737064720122281703160260093053*t^61 - 744598640374124636689234211428703034012541592904035690132391033697417520099934260197296585470011550246912666357352539485145063625/47809525957094015307847932229251610527929119836338552730901470246737064720122281703160260093053*t^59 + 83453825194313667452623379584731940439466304695549539628165897854412013290748780237481370245686122023632159239113621490197576101125/47809525957094015307847932229251610527929119836338552730901470246737064720122281703160260093053*t^57 - 8121366678242791279932799932113196903409641605801511637382903342733585118146553650297781772179620127059074724894763025275081313602125/47809525957094015307847932229251610527929119836338552730901470246737064720122281703160260093053*t^55 + 687451580109587895100905105795436700184221745524406721046890757120001696948769765656682059916589766608999165015232465239661812654724375/47809525957094015307847932229251610527929119836338552730901470246737064720122281703160260093053*t^53 - 50667942559159311120859836125941696508329436435881129024809176319655008086531332364361932687187041044843541751598802528614365660788220000/47809525957094015307847932229251610527929119836338552730901470246737064720122281703160260093053*t^51 + 3252799827992508167306391003413588656721626077421841527546641498009103789250608682913542360465208952255154925193105821859178519854776600000/47809525957094015307847932229251610527929119836338552730901470246737064720122281703160260093053*t^49 - 363684981847304986189075949438266833643562670681958896635002674214715551302503137258016754810684300669669932294559672136979146344411479653125/95619051914188030615695864458503221055858239672677105461802940493474129440244563406320520186106*t^47 + 25598692794836036986177856847516475637312799228273885223516975168369597110163951168335261750479185186095067033620498828209372104290321084375/138377788587826382946014275627356325695887466964800442057601939932668783560411813902055745566*t^45 - 747409246285533972346224909164438100474220544413213828280015090058461611583475117406168301746041411097843143828390001747812383603302027192734375/95619051914188030615695864458503221055858239672677105461802940493474129440244563406320520186106*t^43 + 27378611612171806426944411413522225172942445876831047155862645314965781789531371078904050141262530385758186713643784710559634664382194420866046875/95619051914188030615695864458503221055858239672677105461802940493474129440244563406320520186106*t^41 - 867125589819661355385776349443966682994945587930320660970251453682762589408444369820053927108187501384016192948517256480766772286349639721656234375/95619051914188030615695864458503221055858239672677105461802940493474129440244563406320520186106*t^39 + 23665227608036005989842498340657596621999601243002396638220490407770144822709832063055712838973683862571796124864267413045959538552044383008552796875/95619051914188030615695864458503221055858239672677105461802940493474129440244563406320520186106*t^37 - 554278313068653967303323143721597845057636866624321969348142207550688509248435237943248883480492687100958005780523167649058570579657606325967899921875/95619051914188030615695864458503221055858239672677105461802940493474129440244563406320520186106*t^35 + 11087215346973953245433097704842069248903203480585820138965202141684601885015696872558311991079228562097487350953928241923955832120171852831179679859375/95619051914188030615695864458503221055858239672677105461802940493474129440244563406320520186106*t^33 - 94160900128268588974968610758895934136068411283835956781800114942712923964124757366378331015353853058912811365529523876356800087654145808702034824734375/47809525957094015307847932229251610527929119836338552730901470246737064720122281703160260093053*t^31 + 1348970864038041446072322829803309046592842808035464404667993634467651405456038158919976183775579674123726120170914103355871443842313388750410493785984375/47809525957094015307847932229251610527929119836338552730901470246737064720122281703160260093053*t^29 - 16171683664893006334335950501126901327879654837689646806532538454772097510516255831347175098823887497046936216039776562830406002776668816447161664301453125/47809525957094015307847932229251610527929119836338552730901470246737064720122281703160260093053*t^27 + 160733230837282871461647527236204152605554911669418455324589259855658646925960449807751838649658184972359915914341328282257510452754931748706856399477640625/47809525957094015307847932229251610527929119836338552730901470246737064720122281703160260093053*t^25 - 1310179854362366782099683275186608642248952152598472244992424256721842373293417455183032935417154722249379226873621596249447661127162434710166987682662890625/47809525957094015307847932229251610527929119836338552730901470246737064720122281703160260093053*t^23 + 8647013808481320009818476314663859390938013019802405802038596692084108314227770461166289550596527735721660664185636114228972055872732861971945355949710156250/47809525957094015307847932229251610527929119836338552730901470246737064720122281703160260093053*t^21 - 91022783906041708015250321091925150014630546078505529882754804228225586327170042810462418641018003950452695979724348556634960920713679426063577480180430859375/95619051914188030615695864458503221055858239672677105461802940493474129440244563406320520186106*t^19 + 375197357575722978132045127478618372665295505564648742779932475017724371616058602806181288771783329976019460568294510909259942105070489680761273634086141796875/95619051914188030615695864458503221055858239672677105461802940493474129440244563406320520186106*t^17 - 2370182634244573789184110432078227019767564379860951279566338906691921838193017533190113045995128711824821867156251037195328967142896438774239309153609344921875/191238103828376061231391728917006442111716479345354210923605880986948258880489126812641040372212*t^15 + 5585648619768066761292186971856430783961043977985900270023933806248316510832421073189346385692064987280004131101049220921295214611265751909500249492242263671875/191238103828376061231391728917006442111716479345354210923605880986948258880489126812641040372212*t^13 - 9498491673156314620677537346265330274918793033635868239503823893053142829562617848790648978126843320363883587094988241635359591046857871208481541443125244140625/191238103828376061231391728917006442111716479345354210923605880986948258880489126812641040372212*t^11 + 11156882318591734233114452540903038293083190292583970351009743048241881756350056802670125281740208303797231984297015299578567768301817184623011735687293673828125/191238103828376061231391728917006442111716479345354210923605880986948258880489126812641040372212*t^9 - 8510259066477365944963801344446793766148111143906025034100444500080036135844645534328168323912875632298545590212072092722396347697415812322100868357886447265625/191238103828376061231391728917006442111716479345354210923605880986948258880489126812641040372212*t^7 + 3821086195560418209757955172717264436290216623342159793913900189733475760477668812615741827224962893010952613233540309809626668406353943743410786842624986328125/191238103828376061231391728917006442111716479345354210923605880986948258880489126812641040372212*t^5 - 839466442488762180847823250658374284488739772250184585933158908063748321888707399719361716514848013419580949962910385034208421421492313075844641815655869140625/191238103828376061231391728917006442111716479345354210923605880986948258880489126812641040372212*t^3 + 57586754479490272345920851332252881254062929788805092488938646540124851719334917537492979637197377719147799265069313412113104614318623625103747028562626953125/191238103828376061231391728917006442111716479345354210923605880986948258880489126812641040372212*t
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Computing nodes and weights
  current precision for roots: 53
  current precision for roots: 106
  current precision for roots: 212
 current precision for weights: 53
Linear system for weights solvable: 0
  current precision for roots: 106
  current precision for roots: 212
 current precision for weights: 106
Linear system for weights solvable: 0
  current precision for roots: 212
  current precision for roots: 424
 current precision for weights: 212
Linear system for weights solvable: 0
  current precision for roots: 424
  current precision for roots: 848
 current precision for weights: 424
Linear system for weights solvable: 1
  current precision for roots: 848
  current precision for roots: 1696
 current precision for weights: 848
Linear system for weights solvable: 1
Sufficient bits for target precision reached
Positive weights:   83 out of 85
Indefinite weights: 0 out of 85
Negative weights:   2 out of 85
Extension rule has valid weights: 0
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*** EXTENSION WITH INVALID WEIGHTS ***
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