Starting with polynomial:
P : 16*t^4 - 48*t^2 + 12
Extension levels are: 4 63
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Trying to find an order 63 Kronrod extension for:
P1 : 16*t^4 - 48*t^2 + 12
Solvable: 1
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Ending with final polynomial:
P : 16*t^67 - 83322607446377572467858913592741841096986281702031816791416/5007268306082155904346097000111886187164809621515616675*t^65 + 2400336898339731219876869223233519799955153342026377759706138792/295428830058847198356419723006601285042723767669421383825*t^63 - 732141089716224228622597116751437047454763529161318789945647274068/295428830058847198356419723006601285042723767669421383825*t^61 + 31319634532143738568874333214754318142131681003391610710716409628462/59085766011769439671283944601320257008544753533884276765*t^59 - 84730622390191736740574241248032943467284136157238419162179901863113/1001453661216431180869219400022377237432961924303123335*t^57 + 20973532307860579298535079866035023974473764303000533125985954579711939/2002907322432862361738438800044754474865923848606246670*t^55 - 4129472372348864526336447678599121730897551786798474234620805221864905179/4005814644865724723476877600089508949731847697212493340*t^53 + 658272483385361161117937559701290038791019046697137414748973989771063221347/8011629289731449446953755200179017899463695394424986680*t^51 - 17207376759205676633667604479441650956061507555457340085630456027004070334955/3204651715892579778781502080071607159785478157769994672*t^49 + 1860727761696482809474988784885063358409621654640519891175241971196966137307235/6409303431785159557563004160143214319570956315539989344*t^47 - 167533839826120685280534156557703347580344167951737162345168348403337245493753235/12818606863570319115126008320286428639141912631079978688*t^45 + 12613310085152745214434097177752431562066354759751259873243016640686574213348867485/25637213727140638230252016640572857278283825262159957376*t^43 - 796109474575552551847097623145328823580616224569673292474911665404844698209281488705/51274427454281276460504033281145714556567650524319914752*t^41 + 42169917970195794285788866640445459157065017803017694629706755841781520376615591686675/102548854908562552921008066562291429113135301048639829504*t^39 - 1874172431551510872507968644013560536083483888259765970629443098612037013705661084736475/205097709817125105842016133124582858226270602097279659008*t^37 + 34890519371712794235075551917087707675877075844766824846152470399603137541910733871144225/205097709817125105842016133124582858226270602097279659008*t^35 - 1085328683502808536768046504567260061200547295088600461587109059472499982104416018653524225/410195419634250211684032266249165716452541204194559318016*t^33 + 56185007829097307119738824996497000997421220696611138941881227624790071372918525092985096725/1640781678537000846736129064996662865810164816778237272064*t^31 - 1203592334728014143083624837198110330088276013594991653196930834047043513411173907277804915125/3281563357074001693472258129993325731620329633556474544128*t^29 + 21191537156337494527226013102310983470081853699848832726740038261796597014936210302077519215875/6563126714148003386944516259986651463240659267112949088256*t^27 - 304023452102445701328207707465522151762913191760712014568213979235045184416024150199495426919375/13126253428296006773889032519973302926481318534225898176512*t^25 + 3516068389265075727416783003949432144185280658865214339652150437643785134798915231173459430743125/26252506856592013547778065039946605852962637068451796353024*t^23 - 32349914413035937543177017905925972450508544369138382989151483999978901834314833724874142277748125/52505013713184027095556130079893211705925274136903592706048*t^21 + 232951286826362727210073243688656069381173063628486432011448863875800020023609309413447571995490625/105010027426368054191112260159786423411850548273807185412096*t^19 - 1286536896889023181618108486132322842337241645941658779682774975157990530028100476305838947607528125/210020054852736108382224520319572846823701096547614370824192*t^17 + 5312330850576991740266781333163711503397178736997919567156885985969837451606424728979671191868250625/420040109705472216764449040639145693647402193095228741648384*t^15 - 15877938083364891602641763055043170876232787704269853386623199940407687376157889094332964145396600625/840080219410944433528898081278291387294804386190457483296768*t^13 + 32947201686175199983671440703490836671028443465183481551919005931197324025131629777655141272380039375/1680160438821888867057796162556582774589608772380914966593536*t^11 - 44943836224568244497553408177343977616640020095373517811279891668737465454749527287166278955020746875/3360320877643777734115592325113165549179217544761829933187072*t^9 + 37512513739735277803169275531060296226141388267733806374914585882652917776422260758805988728748040625/6720641755287555468231184650226331098358435089523659866374144*t^7 - 17425269856275595647745040180507813464387273582644125949364467334489824931438315521451854538324715625/13441283510575110936462369300452662196716870179047319732748288*t^5 + 7859806530028783366511497266118875521783013885525938720071165757108952180823568615460391367330540625/53765134042300443745849477201810648786867480716189278930993152*t^3 - 617213899503470314448637907924355289960163446852576800089626660714753737514023354876117167702153125/107530268084600887491698954403621297573734961432378557861986304*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:   65 out of 67
Indefinite weights: 0 out of 67
Negative weights:   2 out of 67
Extension rule has valid weights: 0
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*** EXTENSION WITH INVALID WEIGHTS ***
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