Starting with polynomial:
P : t^6 - 15*t^4 + 45*t^2 - 15
Extension levels are: 6 9 14
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Trying to find an order 9 Kronrod extension for:
P1 : t^6 - 15*t^4 + 45*t^2 - 15
Solvable: 1
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Trying to find an order 14 Kronrod extension for:
P2 : t^15 - 13845/191*t^13 + 360405/191*t^11 - 4272555/191*t^9 + 24327405/191*t^7 - 64538775/191*t^5 + 68923575/191*t^3 - 18129825/191*t
Solvable: 1
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Ending with final polynomial:
P : t^29 - 5854014693425680146857926194995/20786051549784625378492529277*t^27 + 78453037404689669824498799514719/2309561283309402819832503253*t^25 - 5348049295390673020147227801345585/2309561283309402819832503253*t^23 + 2061529668446194757342284203563903345/20786051549784625378492529277*t^21 - 19448722661803419611247787591213138945/6928683849928208459497509759*t^19 + 372477999616173391003825685695228903775/6928683849928208459497509759*t^17 - 14584240008950923529222835020228384649275/20786051549784625378492529277*t^15 + 42978373552081311204338591315086120845700/6928683849928208459497509759*t^13 - 84198708285955979609634839298095383833800/2309561283309402819832503253*t^11 + 954458962589428039586122645048602337619200/6928683849928208459497509759*t^9 - 732802192512000492075154236450371729532000/2309561283309402819832503253*t^7 + 945972462698401386202022601712124822126250/2309561283309402819832503253*t^5 - 590142770649734914392881818035421793439750/2309561283309402819832503253*t^3 + 121899523834517447915058659648570398980000/2309561283309402819832503253*t
-------------------------------------------------
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
-------------------------------------------------
The nodes are:
| (4.3418637687749014379 - 2.6206534265555370374e-419j)  +/-  (1.17e-120, 1.17e-120j)
| (6.3374046744807101947 - 1.4554726469424810013e-429j)  +/-  (3.69e-121, 3.69e-121j)
| (-5.5533529315903281928 + 2.2655788078177626388e-438j)  +/-  (7.44e-121, 7.44e-121j)
| (-6.3374046744807101947 + 5.744607580868485171e-441j)  +/-  (3.85e-121, 3.85e-121j)
| (7.2214377909461346466 + 1.9375180555020617443e-440j)  +/-  (1.31e-121, 1.31e-121j)
| (-4.3418637687749014379 - 1.6948903288883130434e-443j)  +/-  (1.2e-120, 1.2e-120j)
| (-8.2847005401732095193 + 2.9422949157734004469e-448j)  +/-  (2.14e-122, 2.14e-122j)
| (-4.8638143059128204381 - 2.2731778213276522066e-444j)  +/-  (1.14e-120, 1.14e-120j)
| (-2.8497303014851234771 + 1.9630353040383990919e-446j)  +/-  (1.26e-121, 1.26e-121j)
| (8.2847005401732095193 + 7.4264436013629394225e-447j)  +/-  (1.97e-122, 1.97e-122j)
| (4.8638143059128204381 + 3.4073742356721755902e-449j)  +/-  (1.12e-120, 1.12e-120j)
| (-2.4440098084964929991 - 3.8205118544583166319e-455j)  +/-  (3.64e-122, 3.64e-122j)
| (-3.8838698531272594691 + 2.8375965580266568716e-452j)  +/-  (7.53e-121, 7.53e-121j)
| (5.5533529315903281928 - 4.2943409723950749022e-452j)  +/-  (7.51e-121, 7.51e-121j)
| (-2.6358035597536629331e-467 - 8.857236572099392432e-468j)  +/-  (8.06e-466, 8.06e-466j)
| (1.3498952853218839149 + 1.4412446955839436341e-458j)  +/-  (1.08e-123, 1.08e-123j)
| (2.4440098084964929991 + 1.2899240634840165325e-457j)  +/-  (3.72e-122, 3.72e-122j)
| (3.3242574335521189524 - 4.6873790608266860132e-456j)  +/-  (3.08e-121, 3.08e-121j)
| (-0.61670659019259415219 + 1.9833440354485094165e-467j)  +/-  (7.17e-126, 7.17e-126j)
| (2.8497303014851234771 + 2.4460276817723541008e-463j)  +/-  (1.31e-121, 1.31e-121j)
| (-7.2214377909461346466 + 2.2270600398044703193e-469j)  +/-  (1.33e-121, 1.33e-121j)
| (1.1553106934549731694 + 6.4984123602200600942e-472j)  +/-  (3.49e-124, 3.49e-124j)
| (-1.3498952853218839149 + 1.444512992771950444e-470j)  +/-  (8.76e-124, 8.76e-124j)
| (-1.1553106934549731694 + 8.8828438778956160764e-474j)  +/-  (3.61e-124, 3.61e-124j)
| (-3.3242574335521189524 - 3.637356315010838906e-470j)  +/-  (3.02e-121, 3.02e-121j)
| (3.8838698531272594691 + 3.5675973680314749903e-477j)  +/-  (8.09e-121, 8.09e-121j)
| (1.8891758777537106755 + 9.2138531051929846764e-487j)  +/-  (4.73e-123, 4.73e-123j)
| (0.61670659019259415219 + 5.2527316995599886063e-490j)  +/-  (7.87e-126, 7.87e-126j)
| (-1.8891758777537106755 - 6.7472182464416755114e-487j)  +/-  (4.24e-123, 4.24e-123j)
-------------------------------------------------
The weights are:
| (1.386786080265369202e-05 + 1.4234656693519040316e-423j)  +/-  (4.38e-34, 1.56e-94j)
| (6.2784510264571781781e-10 + 3.0667216492992864612e-428j)  +/-  (9.08e-39, 3.23e-99j)
| (5.9450421025892773649e-08 + 1.9291889703483752631e-427j)  +/-  (3.01e-38, 1.07e-98j)
| (6.2784510264571781781e-10 - 5.7305128429094484006e-429j)  +/-  (5.56e-40, 1.98e-100j)
| (1.7987734464733139055e-12 - 3.9902049730423144539e-430j)  +/-  (1.11e-41, 3.95e-102j)
| (1.386786080265369202e-05 + 4.1851678065526723566e-425j)  +/-  (2e-36, 7.11e-97j)
| (6.0880983466646053087e-16 - 5.9295286448650075207e-433j)  +/-  (2.64e-44, 9.39e-105j)
| (1.8153896955021721349e-06 - 4.4328621493032019139e-426j)  +/-  (2.15e-37, 7.63e-98j)
| (0.0026332138376991789718 - 3.8262329229961230241e-423j)  +/-  (4.77e-34, 1.7e-94j)
| (6.0880983466646053087e-16 + 1.8988758372639300407e-432j)  +/-  (2.9e-45, 1.03e-105j)
| (1.8153896955021721349e-06 + 7.8182699304105350093e-425j)  +/-  (9.21e-40, 3.28e-100j)
| (0.0098414704891443031864 + 8.1627887802137321602e-423j)  +/-  (2.37e-34, 8.44e-95j)
| (0.0001112953649127647007 - 1.9201310058644434522e-424j)  +/-  (4.41e-37, 1.57e-97j)
| (5.9450421025892773649e-08 - 1.5757254380935535015e-426j)  +/-  (5.59e-41, 1.99e-101j)
| (0.24711861737595595219 - 4.1614841655849208297e-422j)  +/-  (2.58e-33, 9.16e-94j)
| (0.056361707824534927646 + 1.6003265613253084596e-421j)  +/-  (2.47e-33, 8.8e-94j)
| (0.0098414704891443031864 + 2.9186467378454123737e-422j)  +/-  (4.8e-37, 1.71e-97j)
| (0.00088167117870531143763 + 7.3628768174464593298e-423j)  +/-  (5.53e-39, 1.97e-99j)
| (0.20109430586613203423 + 4.6079738131319540457e-422j)  +/-  (5.81e-35, 2.06e-95j)
| (0.0026332138376991789718 - 1.844118814021252539e-422j)  +/-  (3.92e-38, 1.39e-98j)
| (1.7987734464733139055e-12 + 9.9366867884407697764e-431j)  +/-  (4.25e-46, 1.5e-106j)
| (0.066069237518347228315 - 1.6741930245231504181e-421j)  +/-  (5.47e-36, 1.92e-96j)
| (0.056361707824534927646 + 8.4123846234524730224e-422j)  +/-  (7.93e-37, 2.77e-97j)
| (0.066069237518347228315 - 9.7048128408860893841e-422j)  +/-  (1.42e-36, 4.99e-97j)
| (0.00088167117870531143763 + 9.7735346169235712153e-424j)  +/-  (2.87e-39, 1.03e-99j)
| (0.0001112953649127647007 - 3.4486235807755240211e-423j)  +/-  (2.34e-40, 8.5e-101j)
| (0.03943204590198260876 - 4.7939763555263017522e-422j)  +/-  (3.45e-38, 1.27e-98j)
| (0.20109430586613203423 + 6.1336908133930956822e-422j)  +/-  (1.18e-37, 4.39e-98j)
| (0.03943204590198260876 - 1.8870250269641085384e-422j)  +/-  (1.83e-38, 5.7e-99j)
