Starting with polynomial:
P : t^19 - 171*t^17 + 11628*t^15 - 406980*t^13 + 7936110*t^11 - 87297210*t^9 + 523783260*t^7 - 1571349780*t^5 + 1964187225*t^3 - 654729075*t
Extension levels are: 19 30
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Trying to find an order 30 Kronrod extension for:
P1 : t^19 - 171*t^17 + 11628*t^15 - 406980*t^13 + 7936110*t^11 - 87297210*t^9 + 523783260*t^7 - 1571349780*t^5 + 1964187225*t^3 - 654729075*t
Solvable: 1
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Ending with final polynomial:
P : t^49 - 508459003846665173892104821/562980976816838068369236*t^47 + 69695552024580368636390261071/187660325605612689456412*t^45 - 17333777911146372095497259221905/187660325605612689456412*t^43 + 2921338812712812373173068612774085/187660325605612689456412*t^41 - 354299326896519962998804385259209145/187660325605612689456412*t^39 + 32053393033560936285970936945445405145/187660325605612689456412*t^37 - 2213098628452328152227449811537700041735/187660325605612689456412*t^35 + 118338964378920344093874896173154920748775/187660325605612689456412*t^33 - 2472796073862628820131845286664086491076275/93830162802806344728206*t^31 + 81171330628738038070311843216197571242440875/93830162802806344728206*t^29 - 2096212521352263366090217845806908686176383125/93830162802806344728206*t^27 + 42528966930388751954348839757923343588659241625/93830162802806344728206*t^25 - 675003892812558233053993602422642092880085965625/93830162802806344728206*t^23 + 8320796282758524668084000659739644470724689515625/93830162802806344728206*t^21 - 78829654490879828887331583996501530071796615844375/93830162802806344728206*t^19 + 565723897069750439673616934125123462452633613063125/93830162802806344728206*t^17 - 6032796822735906101345444413298188491227818512631875/187660325605612689456412*t^15 + 23286373255888186972291480184551526799518068928896875/187660325605612689456412*t^13 - 62825941893167911091688074162240345502106624050403125/187660325605612689456412*t^11 + 112894443073755215381471118467630892035025589767365625/187660325605612689456412*t^9 - 126398107944766690649487755279149848005104169906053125/187660325605612689456412*t^7 + 80686630332735052049702791722601015468930119162253125/187660325605612689456412*t^5 - 26254929916610514408525411021666467971748712459046875/187660325605612689456412*t^3 + 3340577900007093776974752838525229360961985948171875/187660325605612689456412*t
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Computing nodes and weights
  current precision for roots: 53
  current precision for roots: 106
 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: 1
  current precision for roots: 424
  current precision for roots: 848
 current precision for weights: 424
Linear system for weights solvable: 1
Sufficient bits for target precision reached
Positive weights:   45 out of 49
Indefinite weights: 0 out of 49
Negative weights:   4 out of 49
Extension rule has valid weights: 0
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*** EXTENSION WITH INVALID WEIGHTS ***
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