Starting with polynomial:
P : t
Extension levels are: 1 2 18
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Trying to find an order 2 Kronrod extension for:
P1 : t
Solvable: 1
-------------------------------------------------
Trying to find an order 18 Kronrod extension for:
P2 : t^3 - 3/5*t
Solvable: 1
-------------------------------------------------
Ending with final polynomial:
P : t^21 - 492974097/95285320*t^19 + 1092720951/95285320*t^17 - 62676676797/4406946050*t^15 + 104814789093/9695281310*t^13 - 239868945099/46239033940*t^11 + 190151996979/121902907660*t^9 - 17182210131/60951453830*t^7 + 42668603943/1523786345750*t^5 - 107290416779/84113006285400*t^3 + 479989951/28037668761800*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: 1
  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:
| (-0.9940396115810441603 - 4.3662460569446846808e-401j)  +/-  (1.87e-121, 1.87e-121j)
| (0.96863851499355040942 + 2.5592103832992607718e-406j)  +/-  (4.12e-121, 4.12e-121j)
| (-0.92316618973895636051 + 8.063302269604359981e-418j)  +/-  (4.26e-121, 4.26e-121j)
| (-0.14788136810434884046 - 1.9795372511577519622e-419j)  +/-  (8.55e-127, 8.55e-127j)
| (0.92316618973895636051 - 3.0310852386572812395e-420j)  +/-  (4.18e-121, 4.18e-121j)
| (0.67401253888417823604 + 1.5474970424493550304e-425j)  +/-  (1.68e-122, 1.68e-122j)
| (0.9940396115810441603 + 4.3269897821064351681e-429j)  +/-  (1.76e-121, 1.76e-121j)
| (-0.85815313192946415361 + 1.3007358832567270592e-432j)  +/-  (2.26e-121, 2.26e-121j)
| (-0.55841853871864983226 - 2.1214951297019981206e-433j)  +/-  (2.29e-123, 2.29e-123j)
| (0.55841853871864983226 + 6.2844959704900741534e-434j)  +/-  (2.15e-123, 2.15e-123j)
| (0.85815313192946415361 - 3.7625810438909711862e-440j)  +/-  (2.44e-121, 2.44e-121j)
| (0.14788136810434884046 - 1.3444964872796727971e-445j)  +/-  (8.55e-127, 8.55e-127j)
| (-0.43027365915780572809 + 8.3020158279265773787e-446j)  +/-  (2.36e-124, 2.36e-124j)
| (-0.77459666924148337704 + 1.2358037794783367416e-446j)  +/-  (8.12e-122, 8.12e-122j)
| (-4.3780769670427979771e-451 - 1.4785602163954316587e-448j)  +/-  (3.1e-447, 3.1e-447j)
| (0.77459666924148337704 - 2.1625708094026984904e-453j)  +/-  (7.17e-122, 7.17e-122j)
| (0.43027365915780572809 - 1.1590198717801013101e-458j)  +/-  (2.38e-124, 2.38e-124j)
| (-0.96863851499355040942 + 1.4561591106607977986e-455j)  +/-  (4.39e-121, 4.39e-121j)
| (-0.67401253888417823604 - 2.1048555026871688574e-459j)  +/-  (1.61e-122, 1.61e-122j)
| (-0.29239730601748887918 + 9.8395353669618657024e-464j)  +/-  (1.6e-125, 1.6e-125j)
| (0.29239730601748887918 - 4.2256704625308212626e-474j)  +/-  (1.4e-125, 1.4e-125j)
-------------------------------------------------
The weights are:
| (0.015291840277723014901 - 5.5043116742697927593e-401j)  +/-  (1.62e-46, 2.05e-104j)
| (0.035490755351857458095 + 1.1471343491540329871e-402j)  +/-  (5.6e-47, 7.08e-105j)
| (0.055367125232500208795 - 5.8594399901774350833e-401j)  +/-  (4.28e-47, 5.41e-105j)
| (0.14675499170995396802 + 1.5076433600327074712e-401j)  +/-  (7.73e-48, 9.76e-106j)
| (0.055367125232500208795 - 2.1656934167553912269e-402j)  +/-  (2.85e-47, 3.61e-105j)
| (0.10846462230386839226 + 5.6356865416632880193e-402j)  +/-  (7.26e-48, 9.18e-106j)
| (0.015291840277723014901 - 3.3594746060296241001e-403j)  +/-  (1.07e-47, 1.35e-105j)
| (0.0744936852448249456 + 4.4738837870152125258e-401j)  +/-  (1.05e-48, 1.34e-106j)
| (0.12231217207212463331 - 2.4487701637357802669e-401j)  +/-  (6.76e-49, 8.57e-107j)
| (0.12231217207212463331 - 6.8711728489405491582e-402j)  +/-  (2.12e-48, 2.67e-106j)
| (0.0744936852448249456 + 3.2820525427469728785e-402j)  +/-  (4e-48, 5.05e-106j)
| (0.14675499170995396802 + 1.1171540065920442153e-401j)  +/-  (3.34e-49, 4.23e-107j)
| (0.13350621081956087845 + 2.0660332209126569496e-401j)  +/-  (1.69e-49, 2.16e-107j)
| (0.09236626392075145478 - 3.5812371811713583572e-401j)  +/-  (4.63e-50, 5.94e-108j)
| (0.14844531756757397745 - 1.297200942236229415e-401j)  +/-  (2.01e-49, 2.52e-107j)
| (0.09236626392075145478 - 4.4432466864505551247e-402j)  +/-  (2.07e-49, 2.6e-107j)
| (0.13350621081956087845 + 8.1776156540589185652e-402j)  +/-  (8.45e-50, 1.07e-107j)
| (0.035490755351857458095 + 8.8646387319010771929e-401j)  +/-  (7.2e-51, 9.38e-109j)
| (0.10846462230386839226 + 2.9375097170879787781e-401j)  +/-  (2.53e-50, 3.29e-108j)
| (0.14172967428304805707 - 1.7591071128639867166e-401j)  +/-  (2e-50, 2.69e-108j)
| (0.14172967428304805707 - 9.5943862657446998765e-402j)  +/-  (1.64e-50, 1.84e-108j)
