Starting with polynomial:
P : 128*t^7 - 1344*t^5 + 3360*t^3 - 1680*t
Extension levels are: 7 14
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Trying to find an order 14 Kronrod extension for:
P1 : 128*t^7 - 1344*t^5 + 3360*t^3 - 1680*t
Solvable: 1
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Ending with final polynomial:
P : 128*t^21 - 56224/5*t^19 + 5966128/15*t^17 - 36835372/5*t^15 + 77921662*t^13 - 482270789*t^11 + 3448558113/2*t^9 - 13584319749/4*t^7 + 26812306521/8*t^5 - 22041464445/16*t^3 + 4851751905/32*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
Positive weights:   21 out of 21
Indefinite weights: 0 out of 21
Negative weights:   0 out of 21
Extension rule has valid weights: 1
-------------------------------------------------
The nodes are:
| (3.77451174254372318 - 3.3776456898692873349e-373j)  +/-  (7.25e-123, 7.25e-123j)
| (-5.2012355362882988282 - 2.3293003400260636818e-380j)  +/-  (1.07e-123, 1.07e-123j)
| (-1.2317848019055522856 + 5.0442296335206714993e-383j)  +/-  (7.41e-125, 7.41e-125j)
| (2.6519613568352334924 + 4.8691951701807019093e-388j)  +/-  (3.72e-123, 3.72e-123j)
| (5.2012355362882988282 + 1.2775652541949484626e-394j)  +/-  (9.96e-124, 9.96e-124j)
| (4.4239129782805977431 - 3.4793032740528442181e-402j)  +/-  (4.38e-123, 4.38e-123j)
| (2.1470001357686231411 - 2.0324972952121312827e-411j)  +/-  (1.24e-123, 1.24e-123j)
| (-4.4239129782805977431 + 5.3174369170355789568e-415j)  +/-  (4.53e-123, 4.53e-123j)
| (-2.1470001357686231411 - 8.9117400446977130623e-415j)  +/-  (1.43e-123, 1.43e-123j)
| (-2.6519613568352334924 - 5.9917388423445172126e-416j)  +/-  (3.27e-123, 3.27e-123j)
| (0.81628788285896466304 - 3.1052769440424314229e-418j)  +/-  (1.35e-125, 1.35e-125j)
| (1.6263671145473628262e-420 + 1.5811902502543805255e-420j)  +/-  (4.76e-419, 4.76e-419j)
| (-0.40983833042411460518 + 2.8777662554629725564e-420j)  +/-  (1.06e-126, 1.06e-126j)
| (-3.1912901973607786827 - 2.8971019533803689811e-418j)  +/-  (5.9e-123, 5.9e-123j)
| (-3.77451174254372318 + 2.7503674981567624684e-419j)  +/-  (6.46e-123, 6.46e-123j)
| (1.673551628767471445 + 1.100744886826082425e-423j)  +/-  (4.03e-124, 4.03e-124j)
| (1.2317848019055522856 - 7.2931410722998028899e-433j)  +/-  (7.76e-125, 7.76e-125j)
| (-1.673551628767471445 - 4.9176777830184359627e-439j)  +/-  (4.03e-124, 4.03e-124j)
| (-0.81628788285896466304 + 7.2564234763301168418e-454j)  +/-  (1.24e-125, 1.24e-125j)
| (3.1912901973607786827 - 6.8981513894551536112e-475j)  +/-  (7.16e-123, 7.16e-123j)
| (0.40983833042411460518 + 9.1230902215964598248e-492j)  +/-  (1.27e-126, 1.27e-126j)
-------------------------------------------------
The weights are:
| (2.2389116381951573299e-07 + 3.3444283927022518603e-379j)  +/-  (8.27e-48, 1.08e-108j)
| (8.9857923030471386195e-13 + 7.4613955740984718682e-384j)  +/-  (2.67e-51, 3.49e-112j)
| (0.052787547252404605877 - 5.9518392650963980736e-377j)  +/-  (1.57e-39, 2.05e-100j)
| (0.00025947386068715770253 + 5.1893424286097741174e-378j)  +/-  (1.67e-45, 2.18e-106j)
| (8.9857923030471386195e-13 - 4.6940831272925028649e-383j)  +/-  (2.8e-51, 3.66e-112j)
| (1.2438118603265630208e-09 + 5.8384047335400912793e-381j)  +/-  (1.31e-49, 1.71e-110j)
| (0.0027474591190104329973 - 1.7989437354821183288e-377j)  +/-  (3.55e-45, 4.64e-106j)
| (1.2438118603265630208e-09 - 4.6246290578406084219e-382j)  +/-  (9.03e-52, 1.18e-112j)
| (0.0027474591190104329973 - 4.9443487573985944495e-378j)  +/-  (1.62e-47, 2.12e-108j)
| (0.00025947386068715770253 + 9.064534311444813148e-379j)  +/-  (5.45e-49, 7.12e-110j)
| (0.11811431940204569808 + 2.001215593533378662e-376j)  +/-  (1e-44, 1.31e-105j)
| (0.23197318701315581799 + 2.5856139884070316451e-376j)  +/-  (6.35e-45, 8.28e-106j)
| (0.19440564429208587453 - 2.070919474676453938e-376j)  +/-  (3.13e-45, 4.08e-106j)
| (1.1906924634301593617e-05 - 1.1817126866262519562e-379j)  +/-  (1.91e-50, 2.5e-111j)
| (2.2389116381951573299e-07 + 1.0017521402355512404e-380j)  +/-  (1.27e-51, 1.67e-112j)
| (0.015686830506679761153 + 5.175731959367602318e-377j)  +/-  (2.27e-48, 2.93e-109j)
| (0.052787547252404605877 - 1.17183934915693164e-376j)  +/-  (1.06e-47, 1.34e-108j)
| (0.015686830506679761153 + 1.9959400119934209267e-377j)  +/-  (1.5e-48, 1.89e-109j)
| (0.11811431940204569808 + 1.2895451100207918799e-376j)  +/-  (1.24e-47, 1.51e-108j)
| (1.1906924634301593617e-05 - 1.4113978350834167484e-378j)  +/-  (2.95e-51, 4.2e-112j)
| (0.19440564429208587453 - 2.5754215134228098625e-376j)  +/-  (1.08e-47, 1.1e-108j)
