Starting with polynomial:
P : 64*t^6 - 480*t^4 + 720*t^2 - 120
Extension levels are: 6 17
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Trying to find an order 17 Kronrod extension for:
P1 : 64*t^6 - 480*t^4 + 720*t^2 - 120
Solvable: 1
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Ending with final polynomial:
P : 64*t^23 - 3672356384/563719*t^21 + 153536216816/563719*t^19 - 37969183021304/6200909*t^17 + 505394895435400/6200909*t^15 - 318462785190060/476993*t^13 + 1619167392847410/476993*t^11 - 457558631596185/43363*t^9 + 3331162062959535/173452*t^7 - 6488419347243225/346904*t^5 + 5608578115263375/693808*t^3 - 1359793918644525/1387616*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:
| (-1.7257543731049377316 + 2.7543921790556769263e-450j)  +/-  (6.99e-123, 6.99e-123j)
| (2.8643489840494312948 + 4.089490571523712467e-451j)  +/-  (1.98e-122, 1.98e-122j)
| (-5.4271434410183854834 + 1.3418184148564570824e-455j)  +/-  (2.34e-123, 2.34e-123j)
| (5.4271434410183854834 - 8.9614938539698554905e-460j)  +/-  (2.11e-123, 2.11e-123j)
| (3.9984736061714746907 - 3.9629717265333360947e-459j)  +/-  (2.17e-122, 2.17e-122j)
| (4.6499114666363360303 - 4.559411575743699808e-468j)  +/-  (1.08e-122, 1.08e-122j)
| (-3.9984736061714746907 - 1.5743633735260947229e-478j)  +/-  (1.97e-122, 1.97e-122j)
| (-3.410856526609457356 - 9.8531338107728925883e-487j)  +/-  (2.46e-122, 2.46e-122j)
| (-1.9059385507405322109 - 9.6856126007307706884e-492j)  +/-  (1.05e-122, 1.05e-122j)
| (-4.6499114666363360303 + 1.5865688011492722313e-492j)  +/-  (9.93e-123, 9.93e-123j)
| (1.3358490740136969497 + 5.7594620863637964561e-493j)  +/-  (6.81e-124, 6.81e-124j)
| (0.43607741192761650868 - 1.1930940353343080146e-496j)  +/-  (2.26e-126, 2.26e-126j)
| (-2.8643489840494312948 - 7.0618931630526128023e-493j)  +/-  (1.91e-122, 1.91e-122j)
| (-0.88130005666902968235 + 8.8638342430514421867e-499j)  +/-  (3.7e-125, 3.7e-125j)
| (3.410856526609457356 - 1.2290195090993776948e-494j)  +/-  (2.4e-122, 2.4e-122j)
| (1.7257543731049377316 + 2.3066391208490986502e-499j)  +/-  (6.32e-123, 6.32e-123j)
| (4.9033607927484387201e-513 - 4.9033607927484387201e-513j)  +/-  (1.59e-511, 1.59e-511j)
| (-2.3506049736744922228 - 6.573912248211627323e-505j)  +/-  (1.22e-122, 1.22e-122j)
| (-1.3358490740136969497 - 4.916717339631526764e-508j)  +/-  (6.07e-124, 6.07e-124j)
| (-0.43607741192761650868 + 5.2871743909143871813e-510j)  +/-  (2.8e-126, 2.8e-126j)
| (2.3506049736744922228 + 1.1848948138349880319e-507j)  +/-  (1.16e-122, 1.16e-122j)
| (0.88130005666902968235 + 1.0309186119029402963e-513j)  +/-  (4.03e-125, 4.03e-125j)
| (1.9059385507405322109 - 4.8510432975409168681e-515j)  +/-  (1.1e-122, 1.1e-122j)
-------------------------------------------------
The weights are:
| (0.0064479319791773840221 - 2.9198056343783906735e-452j)  +/-  (2.3e-37, 1.72e-97j)
| (8.1727273289242646877e-05 - 1.7002522745703893909e-454j)  +/-  (1.37e-42, 1.02e-102j)
| (8.1319240511696899801e-14 + 9.9682040206261158204e-461j)  +/-  (5.27e-49, 3.94e-109j)
| (8.1319240511696899801e-14 - 1.41281332375260494e-461j)  +/-  (4.61e-49, 3.45e-109j)
| (3.9466115578765566136e-08 + 5.1860567530108716941e-458j)  +/-  (1.65e-46, 1.24e-106j)
| (1.6023860780581540641e-10 + 1.3721198529660131559e-460j)  +/-  (1e-47, 7.49e-108j)
| (3.9466115578765566136e-08 + 3.1844270209096366667e-457j)  +/-  (2.33e-48, 1.74e-108j)
| (2.8227488955031542005e-06 - 6.4485904652292674529e-456j)  +/-  (2.37e-47, 1.77e-107j)
| (0.0047763690017800571097 + 6.0058522508822085763e-452j)  +/-  (1.29e-43, 9.64e-104j)
| (1.6023860780581540641e-10 - 9.380723128834791159e-459j)  +/-  (5.31e-50, 3.97e-110j)
| (0.042968147381901913982 - 8.1175566014115713884e-453j)  +/-  (3.12e-44, 2.33e-104j)
| (0.20507053765847871062 - 1.3031692805885702553e-452j)  +/-  (1.17e-43, 8.79e-104j)
| (8.1727273289242646877e-05 + 1.0205592214957918956e-454j)  +/-  (1.07e-46, 8e-107j)
| (0.11704678515779725789 + 2.3463463108529456088e-452j)  +/-  (2.83e-44, 2.12e-104j)
| (2.8227488955031542005e-06 - 3.5539356298463207145e-456j)  +/-  (1.46e-48, 1.09e-108j)
| (0.0064479319791773840221 + 9.389489324767889654e-453j)  +/-  (8.18e-46, 6.11e-106j)
| (0.24498169312446805879 + 1.6530928304977981349e-452j)  +/-  (2.5e-44, 1.88e-104j)
| (0.0011147926100103953674 - 1.7449034371664766692e-453j)  +/-  (2.35e-46, 1.76e-106j)
| (0.042968147381901913982 - 4.2298885092347068859e-452j)  +/-  (4.63e-45, 3.47e-105j)
| (0.20507053765847871062 - 1.9454596453444968919e-452j)  +/-  (1.71e-45, 1.31e-105j)
| (0.0011147926100103953674 + 8.7335357447142960897e-454j)  +/-  (1.22e-47, 9.14e-108j)
| (0.11704678515779725789 + 9.7221779466283083735e-453j)  +/-  (3.2e-46, 2.46e-106j)
| (0.0047763690017800571097 - 6.1146333480673048778e-453j)  +/-  (9.8e-47, 7.24e-107j)
