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*t
Solvable: 1
-------------------------------------------------
Ending with final polynomial:
P : t^21 - 12952203/68336*t^19 + 987853833/68336*t^17 - 9840668841/17084*t^15 + 222748598835/17084*t^13 - 5840004786525/34168*t^11 + 43360655152815/34168*t^9 - 85340399389245/17084*t^7 + 155352674512035/17084*t^5 - 385274669454675/68336*t^3 + 24027902323425/68336*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
-------------------------------------------------
The nodes are:
| (3.1818251743752155138 + 5.5874582176171704538e-429j)  +/-  (2.82e-123, 2.82e-123j)
| (4.7297437340900698938 + 4.8711890744784114813e-435j)  +/-  (1.21e-122, 1.21e-122j)
| (6.5070736248349749985 + 7.0852432225162419364e-444j)  +/-  (9.11e-123, 9.11e-123j)
| (7.6160439823731721235 - 1.8656630189042818967e-450j)  +/-  (1.76e-123, 1.76e-123j)
| (-5.5746342077876410169 - 2.4428368431562272744e-458j)  +/-  (1.21e-122, 1.21e-122j)
| (-6.5070736248349749985 - 4.9653314094588532644e-459j)  +/-  (7.79e-123, 7.79e-123j)
| (5.5746342077876410169 + 2.099312912087382814e-460j)  +/-  (1.3e-122, 1.3e-122j)
| (-7.6160439823731721235 + 2.2503400861975684476e-468j)  +/-  (1.74e-123, 1.74e-123j)
| (3.9411862773377744103e-470 + 7.4863219728842528627e-471j)  +/-  (8.42e-469, 8.42e-469j)
| (-4.7297437340900698938 - 2.2008820623250944158e-468j)  +/-  (1.19e-122, 1.19e-122j)
| (1.0205995233277591225 - 2.542451539694368198e-469j)  +/-  (1.07e-125, 1.07e-125j)
| (-0.2645038383451557269 + 2.9432112595008655408e-473j)  +/-  (7.67e-127, 7.67e-127j)
| (-3.938157784076607613 + 1.8413937110723363896e-472j)  +/-  (7.1e-123, 7.1e-123j)
| (-2.4493260905130791576 - 4.999685793382880566e-474j)  +/-  (6.35e-124, 6.35e-124j)
| (3.938157784076607613 - 2.2640086611545119544e-473j)  +/-  (7.05e-123, 7.05e-123j)
| (2.4493260905130791576 + 2.6268674591757942083e-482j)  +/-  (6.73e-124, 6.73e-124j)
| (1.7320508075688772935 + 2.6006911010747498805e-487j)  +/-  (1.1e-124, 1.1e-124j)
| (-1.7320508075688772935 - 1.4400572905838358109e-491j)  +/-  (1.13e-124, 1.13e-124j)
| (-1.0205995233277591225 + 7.2872217296944816425e-494j)  +/-  (1.28e-125, 1.28e-125j)
| (-3.1818251743752155138 + 7.2002864529191790545e-492j)  +/-  (2.97e-123, 2.97e-123j)
| (0.2645038383451557269 + 1.2875115489219151237e-498j)  +/-  (7.67e-127, 7.67e-127j)
-------------------------------------------------
The weights are:
| (0.001876737515456819725 - 1.9982229212032385168e-431j)  +/-  (6.67e-38, 2.57e-99j)
| (4.508668151637647589e-06 + 2.2329957038999310848e-433j)  +/-  (1.49e-41, 5.77e-103j)
| (2.5409011476331484289e-10 + 5.6712402260653641489e-436j)  +/-  (9.57e-45, 3.69e-106j)
| (1.2874282197399546648e-13 - 8.1788471145325766367e-438j)  +/-  (2.41e-46, 9.29e-108j)
| (6.2739849087170433288e-08 + 3.9504208890843456365e-435j)  +/-  (2.98e-46, 1.15e-107j)
| (2.5409011476331484289e-10 - 1.9463802807799983576e-436j)  +/-  (1.18e-47, 4.56e-109j)
| (6.2739849087170433288e-08 - 1.4456525335588808715e-434j)  +/-  (4.53e-45, 1.75e-106j)
| (1.2874282197399546648e-13 + 3.3586993555637885232e-438j)  +/-  (2.6e-49, 1e-110j)
| (-0.24463152944439541952 + 1.0854768684765947237e-429j)  +/-  (2.69e-40, 1.04e-101j)
| (4.508668151637647589e-06 - 4.3689141728941494471e-434j)  +/-  (4.25e-46, 1.64e-107j)
| (0.16919086035322270515 + 1.4438179312543291757e-430j)  +/-  (5.54e-41, 2.15e-102j)
| (0.37331864421127729351 - 5.6755149504377381097e-430j)  +/-  (2.13e-40, 8.28e-102j)
| (0.0001320045381790025732 + 3.1551802853591100524e-433j)  +/-  (1.34e-45, 5.16e-107j)
| (0.014377034198887046646 + 6.6982709913092644436e-432j)  +/-  (3.5e-44, 1.36e-105j)
| (0.0001320045381790025732 - 2.9702312234187419339e-432j)  +/-  (1.27e-45, 4.95e-107j)
| (0.014377034198887046646 + 5.1493547072214294292e-431j)  +/-  (2.19e-44, 8.51e-106j)
| (0.063415912242955259759 - 7.7348330218070202751e-431j)  +/-  (9.48e-44, 3.69e-105j)
| (0.063415912242955259759 - 2.2820606146733429546e-431j)  +/-  (1.04e-44, 4.03e-106j)
| (0.16919086035322270515 + 7.4252761258189878648e-431j)  +/-  (4.37e-44, 1.83e-105j)
| (0.001876737515456819725 - 1.6478267054756483044e-432j)  +/-  (4.98e-46, 1.86e-107j)
| (0.37331864421127729351 - 6.704675123928340877e-430j)  +/-  (2.07e-43, 9.19e-105j)
