Starting with polynomial:
P : t^6 - 15*t^4 + 45*t^2 - 15
Extension levels are: 6 16
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Trying to find an order 16 Kronrod extension for:
P1 : t^6 - 15*t^4 + 45*t^2 - 15
Solvable: 1
-------------------------------------------------
Ending with final polynomial:
P : t^22 - 5235757/25259*t^20 + 4806478961/277849*t^18 - 210162507107/277849*t^16 + 5251767962010/277849*t^14 - 5911194422910/21373*t^12 + 4541750070270/1943*t^10 - 21104415208170/1943*t^8 + 1686288299535/67*t^6 - 46953925305525/1943*t^4 + 12547692947475/1943*t^2 - 263693655225/1943
-------------------------------------------------
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:
| (-3.3242574335521189524 + 4.7310314931109125093e-456j)  +/-  (4.59e-123, 4.59e-123j)
| (4.899672545233068218 - 3.4185386100654050791e-465j)  +/-  (1.53e-122, 1.53e-122j)
| (-8.0151746090914415033 - 7.981654591797153192e-464j)  +/-  (1.63e-123, 1.63e-123j)
| (4.0898598585794994525 - 1.747253067366762596e-465j)  +/-  (1e-122, 1e-122j)
| (3.3242574335521189524 - 2.4669662307590047069e-466j)  +/-  (4.15e-123, 4.15e-123j)
| (6.761819399805724654 - 1.2170630514538409749e-465j)  +/-  (8.26e-123, 8.26e-123j)
| (-2.5919688551740525513 + 1.4164778037076562712e-466j)  +/-  (1.19e-123, 1.19e-123j)
| (-6.761819399805724654 + 1.456276404440532429e-474j)  +/-  (8.74e-123, 8.74e-123j)
| (8.0151746090914415033 - 4.8074310155886106716e-480j)  +/-  (1.83e-123, 1.83e-123j)
| (2.5919688551740525513 + 3.3680130740790383535e-480j)  +/-  (1.15e-123, 1.15e-123j)
| (5.7749520542045192017 - 3.9640220654853456415e-481j)  +/-  (1.54e-122, 1.54e-122j)
| (-4.0898598585794994525 - 4.1986415095701632091e-486j)  +/-  (1.07e-122, 1.07e-122j)
| (-5.7749520542045192017 - 1.9676297707645461672e-495j)  +/-  (1.81e-122, 1.81e-122j)
| (-1.8891758777537106755 - 3.8138283748192151439e-505j)  +/-  (2.19e-124, 2.19e-124j)
| (-4.899672545233068218 + 1.3232129734040100536e-508j)  +/-  (1.6e-122, 1.6e-122j)
| (0.15145144509363252271 + 5.414488507893593993e-517j)  +/-  (5.31e-127, 5.31e-127j)
| (1.8891758777537106755 + 2.2307692652521607251e-514j)  +/-  (2.16e-124, 2.16e-124j)
| (-0.15145144509363252271 - 1.0575172866979675768e-517j)  +/-  (5.31e-127, 5.31e-127j)
| (-1.2216989172869496403 + 2.1573352648638538566e-517j)  +/-  (3.03e-125, 3.03e-125j)
| (-0.61670659019259415219 - 3.9656898251173784129e-520j)  +/-  (3.36e-126, 3.36e-126j)
| (1.2216989172869496403 + 3.2434230747419965047e-522j)  +/-  (2.97e-125, 2.97e-125j)
| (0.61670659019259415219 - 1.3079335510124461185e-525j)  +/-  (3.36e-126, 3.36e-126j)
-------------------------------------------------
The weights are:
| (0.0011885862908873445945 + 1.2347947812532028734e-458j)  +/-  (7.15e-42, 5.55e-103j)
| (2.046503838244422061e-06 - 1.4736905329298829243e-461j)  +/-  (9.31e-46, 7.23e-107j)
| (7.0159799634164587553e-15 + 1.0488417583418838828e-465j)  +/-  (1.18e-50, 9.15e-112j)
| (7.3063547573155595834e-05 + 1.3110789268519058743e-460j)  +/-  (2.04e-44, 1.58e-105j)
| (0.0011885862908873445945 - 8.4578876445047841999e-460j)  +/-  (3.31e-43, 2.57e-104j)
| (5.0480560114371132127e-11 - 4.0094119081033062377e-464j)  +/-  (1.3e-49, 1.01e-110j)
| (0.0099512889684200836902 - 3.4711669568616009506e-458j)  +/-  (1.66e-43, 1.29e-104j)
| (5.0480560114371132127e-11 - 1.1763929482700906512e-463j)  +/-  (9.07e-51, 7.04e-112j)
| (7.0159799634164587553e-15 + 4.3388679432231596806e-466j)  +/-  (9.53e-52, 7.4e-113j)
| (0.0099512889684200836902 + 4.2964818991234543687e-459j)  +/-  (2.77e-44, 2.15e-105j)
| (2.1023372687862855947e-08 + 1.0672671764278964788e-462j)  +/-  (2.26e-48, 1.76e-109j)
| (7.3063547573155595834e-05 + 1.2696528383949232851e-459j)  +/-  (2.74e-48, 2.13e-109j)
| (2.1023372687862855947e-08 + 3.9626673740561462542e-462j)  +/-  (7e-51, 5.43e-112j)
| (0.046030784417677134771 + 6.7091186913107954606e-458j)  +/-  (2.13e-46, 1.66e-107j)
| (2.046503838244422061e-06 - 7.6929107080233206935e-461j)  +/-  (8.27e-50, 6.42e-111j)
| (0.13802972841096064994 + 7.2663334778587153411e-457j)  +/-  (1.21e-44, 9.36e-106j)
| (0.046030784417677134771 - 1.8467930661570732812e-458j)  +/-  (4.98e-47, 3.87e-108j)
| (0.13802972841096064994 - 7.9600391186744726078e-457j)  +/-  (8.77e-45, 6.78e-106j)
| (0.12173239414340875558 - 1.5607292350008152261e-457j)  +/-  (6.09e-46, 4.72e-107j)
| (0.18299208664337436745 + 3.9055744112479670255e-457j)  +/-  (2.24e-45, 1.74e-106j)
| (0.12173239414340875558 + 7.2185570900696873937e-458j)  +/-  (9.69e-47, 7.48e-108j)
| (0.18299208664337436745 - 2.6832372047649825468e-457j)  +/-  (3.88e-46, 2.92e-107j)
