Starting with polynomial:
P : t^6 - 15*t^4 + 45*t^2 - 15
Extension levels are: 6 17
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Trying to find an order 17 Kronrod extension for:
P1 : t^6 - 15*t^4 + 45*t^2 - 15
Solvable: 1
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Ending with final polynomial:
P : t^23 - 114761137/563719*t^21 + 9596013551/563719*t^19 - 4746147877663/6200909*t^17 + 126348723858850/6200909*t^15 - 159231392595030/476993*t^13 + 1619167392847410/476993*t^11 - 915117263192370/43363*t^9 + 3331162062959535/43363*t^7 - 6488419347243225/43363*t^5 + 5608578115263375/43363*t^3 - 1359793918644525/43363*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: 1
  current precision for roots: 212
  current precision for roots: 424
 current precision for weights: 212
Linear system for weights solvable: 1
Sufficient bits for target precision reached
Positive weights:   23 out of 23
Indefinite weights: 0 out of 23
Negative weights:   0 out of 23
Extension rule has valid weights: 1
-------------------------------------------------
The nodes are:
| (2.6954041475069820323 - 7.1264631488609116809e-277j)  +/-  (1.55e-122, 1.55e-122j)
| (-3.3242574335521189524 - 1.2624015999493318452e-286j)  +/-  (2.01e-122, 2.01e-122j)
| (3.3242574335521189524 + 7.6960065024344554675e-289j)  +/-  (1.76e-122, 1.76e-122j)
| (-6.5759678599512758816 + 4.4990305888993924109e-298j)  +/-  (1.7e-122, 1.7e-122j)
| (-4.8236795592398821525 + 2.069008111676896126e-296j)  +/-  (3.89e-122, 3.89e-122j)
| (-5.6546956026385571103 - 2.9205924982887132887e-296j)  +/-  (2.76e-122, 2.76e-122j)
| (-7.6751398592323881889 - 7.2951467189111926235e-298j)  +/-  (2.81e-123, 2.81e-123j)
| (-4.0508011806123018395 - 3.096344702925239468e-296j)  +/-  (3.16e-122, 3.16e-122j)
| (6.5759678599512758816 + 2.3742226454721888282e-298j)  +/-  (1.55e-122, 1.55e-122j)
| (2.4405852397696814012 + 1.2475014317979432946e-314j)  +/-  (1.05e-122, 1.05e-122j)
| (5.6546956026385571103 + 2.1172240015739854952e-340j)  +/-  (3.14e-122, 3.14e-122j)
| (4.8236795592398821525 - 3.5022101996721759919e-363j)  +/-  (3.37e-122, 3.37e-122j)
| (-0.61670659019259415219 - 1.4623740883902610865e-374j)  +/-  (3.33e-126, 3.33e-126j)
| (-1.8891758777537106755 - 2.7669046243828431986e-373j)  +/-  (8.65e-124, 8.65e-124j)
| (1.2463464926615190098 - 9.7520492294430052899e-372j)  +/-  (5.83e-125, 5.83e-125j)
| (4.0508011806123018395 + 4.102449355107158802e-376j)  +/-  (3.05e-122, 3.05e-122j)
| (-1.2463464926615190098 + 3.1072454542487336436e-382j)  +/-  (5.64e-125, 5.64e-125j)
| (7.6751398592323881889 + 9.7599406010806976655e-380j)  +/-  (2.89e-123, 2.89e-123j)
| (1.8891758777537106755 + 1.0499804183584397758e-383j)  +/-  (8.65e-124, 8.65e-124j)
| (-2.6954041475069820323 + 3.1238351852051277661e-387j)  +/-  (1.62e-122, 1.62e-122j)
| (-2.4405852397696814012 - 1.8522773721011958668e-392j)  +/-  (9.65e-123, 9.65e-123j)
| (0.61670659019259415219 - 1.4156331818028840694e-394j)  +/-  (3.76e-126, 3.76e-126j)
| (-5.1120087120659702506e-396 + 1.5265026015196994498e-396j)  +/-  (1.23e-394, 1.23e-394j)
-------------------------------------------------
The weights are:
| (0.0047763690017800571097 + 1.7148433947725019442e-278j)  +/-  (8.61e-33, 1.55e-93j)
| (0.0011147926100103953674 - 5.8285911204105050322e-281j)  +/-  (2.3e-35, 4.14e-96j)
| (0.0011147926100103953674 + 5.5793849755892550215e-280j)  +/-  (3.89e-35, 7.01e-96j)
| (1.6023860780581540641e-10 - 1.0301249611803526476e-285j)  +/-  (3.3e-42, 5.95e-103j)
| (2.8227488955031542005e-06 - 4.8536580933273849509e-283j)  +/-  (1.28e-39, 2.31e-100j)
| (3.9466115578765566136e-08 + 2.9654219311236684595e-284j)  +/-  (4.88e-41, 8.78e-102j)
| (8.1319240511696899801e-14 + 1.2606970606317064212e-287j)  +/-  (1.54e-44, 2.77e-105j)
| (8.1727273289242646877e-05 + 5.6687273540728652187e-282j)  +/-  (8.47e-39, 1.53e-99j)
| (1.6023860780581540641e-10 + 2.4611557614867010615e-285j)  +/-  (3.93e-46, 7.07e-107j)
| (0.0064479319791773840221 - 2.1697462541093505063e-278j)  +/-  (3.81e-38, 6.85e-99j)
| (3.9466115578765566136e-08 - 8.3673978497615893897e-284j)  +/-  (5.56e-45, 1e-105j)
| (2.8227488955031542005e-06 + 1.7147715636844839485e-282j)  +/-  (6.5e-44, 1.17e-104j)
| (0.20507053765847871062 + 2.1316392985709104169e-279j)  +/-  (1.06e-38, 1.91e-99j)
| (0.042968147381901913982 + 1.0923210464840270441e-279j)  +/-  (3.89e-40, 7.01e-101j)
| (0.11704678515779725789 - 4.0107258894801956497e-279j)  +/-  (9.28e-39, 1.67e-99j)
| (8.1727273289242646877e-05 - 2.8214905216211519094e-281j)  +/-  (7.13e-43, 1.28e-103j)
| (0.11704678515779725789 - 1.4744141844231650026e-279j)  +/-  (5.66e-40, 1.02e-100j)
| (8.1319240511696899801e-14 - 2.6254635011643817855e-287j)  +/-  (9.86e-49, 1.78e-109j)
| (0.042968147381901913982 + 6.2114334520976947151e-279j)  +/-  (1.56e-40, 2.8e-101j)
| (0.0047763690017800571097 + 6.3141955586037050539e-280j)  +/-  (3.84e-42, 6.91e-103j)
| (0.0064479319791773840221 - 1.0765060636395815193e-279j)  +/-  (6.9e-42, 1.24e-102j)
| (0.20507053765847871062 + 3.3964659182305202274e-279j)  +/-  (6.52e-42, 1.22e-102j)
| (0.24498169312446805879 - 2.8308877522030781819e-279j)  +/-  (6.94e-42, 1.2e-102j)
