Starting with polynomial:
P : 4*t^2 - 2
Extension levels are: 2 21
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Trying to find an order 21 Kronrod extension for:
P1 : 4*t^2 - 2
Solvable: 1
-------------------------------------------------
Ending with final polynomial:
P : 4*t^23 - 54954665174/118894837*t^21 + 2611798498365/118894837*t^19 - 7015431225285/12515246*t^17 + 105322938243075/12515246*t^15 - 1919054458782405/25030492*t^13 + 21142253787983055/50060984*t^11 - 136217711235530925/100121968*t^9 + 956859427232183475/400487872*t^7 - 1604772057804040125/800975744*t^5 + 976872118732985475/1601951488*t^3 - 95174230816890225/3203902976*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:
| (-2.1453612198556774997 - 7.0936139740027590154e-442j)  +/-  (3.1e-123, 3.1e-123j)
| (-0.7071067811865475244 - 1.0022480128053038435e-443j)  +/-  (1.05e-125, 1.05e-125j)
| (4.294875756954426517 + 6.398124107637282845e-440j)  +/-  (2.91e-122, 2.91e-122j)
| (-3.1660300182915619612 + 2.2724348120317124059e-443j)  +/-  (2.47e-122, 2.47e-122j)
| (-5.7096250600094734097 - 1.9357362812570745375e-444j)  +/-  (3.16e-123, 3.16e-123j)
| (1.6573340284571535641 - 7.5635718788886464553e-444j)  +/-  (6.36e-124, 6.36e-124j)
| (4.940323816532283035 + 3.7895587801103748011e-442j)  +/-  (1.39e-122, 1.39e-122j)
| (5.7096250600094734097 + 4.116475863556459788e-446j)  +/-  (3.16e-123, 3.16e-123j)
| (-4.294875756954426517 + 2.33558914244338144e-447j)  +/-  (2.79e-122, 2.79e-122j)
| (2.1453612198556774997 - 7.233027625504346897e-447j)  +/-  (3.2e-123, 3.2e-123j)
| (-4.940323816532283035 - 3.5092551173396563136e-451j)  +/-  (1.39e-122, 1.39e-122j)
| (0.24407628265277317388 - 2.1479970572170234956e-456j)  +/-  (7.27e-127, 7.27e-127j)
| (-3.7113533700493449751 + 5.4069925720990261513e-452j)  +/-  (3.11e-122, 3.11e-122j)
| (-1.6573340284571535641 + 8.2744109424339821541e-454j)  +/-  (5.99e-124, 5.99e-124j)
| (-2.6465515298840171564 - 8.0549889645638381084e-457j)  +/-  (1.05e-122, 1.05e-122j)
| (0.7071067811865475244 + 4.1156490292306002993e-459j)  +/-  (1.18e-125, 1.18e-125j)
| (2.6465515298840171564 - 1.6609982737331678845e-465j)  +/-  (9.96e-123, 9.96e-123j)
| (-0.24407628265277317388 - 1.5476621707110921564e-476j)  +/-  (7.27e-127, 7.27e-127j)
| (-1.1787661557351979068 + 0j)  +/-  (9.62e-125, 9.62e-125j)
| (-2.2403050237117977362e-483 + 2.5258340953613405849e-484j)  +/-  (5.19e-482, 5.19e-482j)
| (3.1660300182915619612 - 5.613605147294079961e-488j)  +/-  (2.22e-122, 2.22e-122j)
| (1.1787661557351979068 + 2.999316676465825004e-499j)  +/-  (9.99e-125, 9.99e-125j)
| (3.7113533700493449751 + 3.0268774467467624581e-503j)  +/-  (3.41e-122, 3.41e-122j)
-------------------------------------------------
The weights are:
| (0.0027937393323819865028 - 5.2887651839801221257e-444j)  +/-  (6.93e-41, 4.56e-101j)
| (0.16035139584624929208 + 3.0330499545661281236e-443j)  +/-  (1.19e-40, 7.85e-101j)
| (3.3498266805198939486e-09 - 1.1220249643657902012e-447j)  +/-  (4.82e-48, 3.17e-108j)
| (1.327836324819410899e-05 + 8.7590822309380857476e-446j)  +/-  (4.65e-45, 3.06e-105j)
| (3.4624099190679959733e-15 + 2.0701838403799884164e-451j)  +/-  (5.6e-51, 3.69e-111j)
| (0.017468927143921027119 + 2.3653502812703261515e-444j)  +/-  (5.03e-41, 3.31e-101j)
| (9.7929090497818569344e-12 - 9.0943026901837074911e-450j)  +/-  (6.86e-50, 4.52e-110j)
| (3.4624099190679959733e-15 + 1.9306542584148597205e-452j)  +/-  (1.56e-51, 1.03e-111j)
| (3.3498266805198939486e-09 + 4.6189035920180092019e-448j)  +/-  (1.58e-49, 1.04e-109j)
| (0.0027937393323819865028 - 5.3457763111661904706e-445j)  +/-  (2.22e-45, 1.46e-105j)
| (9.7929090497818569344e-12 - 1.6465326035611840914e-449j)  +/-  (7.58e-51, 4.99e-111j)
| (0.23938354697111102226 - 7.001041158461626701e-443j)  +/-  (1.56e-44, 1.02e-104j)
| (3.3032510289251758597e-07 - 7.3795698232105400208e-447j)  +/-  (1.31e-48, 8.61e-109j)
| (0.017468927143921027119 + 1.3619404356169280623e-443j)  +/-  (1.63e-45, 1.07e-105j)
| (0.00026092744457752914835 - 9.5747266306141055896e-445j)  +/-  (4.61e-47, 3.03e-107j)
| (0.16035139584624929208 + 1.824484608126347919e-443j)  +/-  (2.19e-45, 1.43e-105j)
| (0.00026092744457752914835 + 1.4566507207265006889e-445j)  +/-  (4.77e-49, 3.14e-109j)
| (0.23938354697111102226 - 7.9336114877899053713e-443j)  +/-  (2.48e-45, 1.63e-105j)
| (0.06675606866209279946 - 2.0284333385297825883e-443j)  +/-  (3.83e-46, 2.51e-106j)
| (0.025943565103384409637 + 1.1848419593080953903e-442j)  +/-  (1.95e-45, 1.28e-105j)
| (1.327836324819410899e-05 - 3.1487631302207966139e-446j)  +/-  (2.16e-50, 1.42e-110j)
| (0.06675606866209279946 - 6.8324408589001916947e-444j)  +/-  (1.29e-47, 7.93e-108j)
| (3.3032510289251758597e-07 + 6.1167643499345401769e-447j)  +/-  (2.38e-51, 1.58e-111j)
