Starting with polynomial:
P : t^3 - 3*t
Extension levels are: 3 6 12
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Trying to find an order 6 Kronrod extension for:
P1 : t^3 - 3*t
Solvable: 1
-------------------------------------------------
Trying to find an order 12 Kronrod extension for:
P2 : t^9 - 117/4*t^7 + 945/4*t^5 - 2205/4*t^3 + 945/4*t
Solvable: 1
-------------------------------------------------
Ending with final polynomial:
P : t^21 - 20774971893/133201492*t^19 + 653412876723/66600746*t^17 - 86530745663355/266402984*t^15 + 1652267603793375/266402984*t^13 - 18783353149157025/266402984*t^11 + 127015854640073685/266402984*t^9 - 497343697084550745/266402984*t^7 + 1061381742497601525/266402984*t^5 - 1073644320567443625/266402984*t^3 + 341241276683382075/266402984*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:
| (4.9504010957537472969 + 1.2049290185483418793e-439j)  +/-  (1.22e-122, 1.22e-122j)
| (-2.1774978119398591001e-450 - 1.7926045816788038091e-450j)  +/-  (5.92e-449, 5.92e-449j)
| (-3.5281823201088102816 + 2.6401499666179983798e-444j)  +/-  (9.92e-123, 9.92e-123j)
| (5.8588069720344226299 - 1.703508926525781751e-450j)  +/-  (6.45e-123, 6.45e-123j)
| (4.1849560176727318607 + 2.0193180957115234269e-462j)  +/-  (1.53e-122, 1.53e-122j)
| (6.9709804504832062107 - 5.7656753904068237773e-472j)  +/-  (1.41e-123, 1.41e-123j)
| (-6.9709804504832062107 - 1.0546507013211434854e-472j)  +/-  (1.39e-123, 1.39e-123j)
| (-2.8612795760570581173 - 8.3013650908998771663e-471j)  +/-  (4.35e-123, 4.35e-123j)
| (-4.9504010957537472969 + 2.4949375445922721738e-471j)  +/-  (1.26e-122, 1.26e-122j)
| (3.5281823201088102816 + 4.0978429522350636929e-479j)  +/-  (9.65e-123, 9.65e-123j)
| (0.74109534999454084186 - 3.5122735488741467458e-486j)  +/-  (5.53e-126, 5.53e-126j)
| (-5.8588069720344226299 - 3.1298379007738350726e-483j)  +/-  (7.03e-123, 7.03e-123j)
| (2.1081419698295089879 - 3.1655290347300279287e-483j)  +/-  (1.89e-123, 1.89e-123j)
| (-2.1081419698295089879 - 4.9573998411208376587e-486j)  +/-  (1.86e-123, 1.86e-123j)
| (-4.1849560176727318607 + 2.2005332177392793447e-486j)  +/-  (1.35e-122, 1.35e-122j)
| (1.7320508075688772935 - 4.1235700138690364084e-486j)  +/-  (1.51e-123, 1.51e-123j)
| (1.5483923302534474053 - 2.8367492195762265661e-490j)  +/-  (6.18e-124, 6.18e-124j)
| (-1.7320508075688772935 + 2.2173609417512471861e-491j)  +/-  (1.41e-123, 1.41e-123j)
| (-0.74109534999454084186 - 1.5668625395364882232e-496j)  +/-  (4.94e-126, 4.94e-126j)
| (-1.5483923302534474053 + 4.5694955336283242207e-495j)  +/-  (5.83e-124, 5.83e-124j)
| (2.8612795760570581173 - 6.5811794516697432056e-505j)  +/-  (4.47e-123, 4.47e-123j)
-------------------------------------------------
The weights are:
| (1.5886493751366877317e-06 - 6.7806300529030895044e-445j)  +/-  (1.36e-46, 1.78e-107j)
| (0.29464113834097234914 - 1.1003987218967315244e-442j)  +/-  (1.24e-44, 1.62e-105j)
| (0.00050644024350559434846 - 1.7726695994486753897e-444j)  +/-  (8.94e-45, 1.17e-105j)
| (1.3884259302050112834e-08 - 8.2298977370865368689e-447j)  +/-  (2.68e-48, 3.5e-109j)
| (4.3825151262043410883e-05 + 3.0993578293119427265e-444j)  +/-  (5.38e-46, 7.04e-107j)
| (1.4361591120110558709e-11 + 5.0974526295728960811e-449j)  +/-  (3.11e-50, 4.07e-111j)
| (1.4361591120110558709e-11 - 8.6422855355608909024e-450j)  +/-  (1.93e-52, 2.52e-113j)
| (0.0046641746195996005792 + 9.2685658623090487919e-444j)  +/-  (5.98e-46, 7.82e-107j)
| (1.5886493751366877317e-06 - 1.9345836287706475892e-446j)  +/-  (5.64e-50, 7.38e-111j)
| (0.00050644024350559434846 - 1.0587611019315172229e-443j)  +/-  (7.94e-48, 1.04e-108j)
| (0.22650451188129539028 + 1.4270505323446738482e-442j)  +/-  (1.62e-45, 2.12e-106j)
| (1.3884259302050112834e-08 + 6.9191951279578494593e-448j)  +/-  (2.15e-51, 2.82e-112j)
| (0.038348317639531055064 - 2.3151596728473929596e-442j)  +/-  (1.32e-46, 1.73e-107j)
| (0.038348317639531055064 - 9.3187416003715979989e-443j)  +/-  (8.75e-47, 1.15e-107j)
| (4.3825151262043410883e-05 + 2.600160208974719492e-445j)  +/-  (4.57e-49, 5.99e-110j)
| (-0.063384688897314300398 + 7.7561790336465910685e-442j)  +/-  (1.52e-46, 1.99e-107j)
| (0.14599524764363841228 - 6.5434903942507693588e-442j)  +/-  (1.95e-46, 2.56e-107j)
| (-0.063384688897314300398 + 3.7344391850662062966e-442j)  +/-  (1.63e-47, 2.17e-108j)
| (0.22650451188129539028 + 1.055316227135095154e-442j)  +/-  (6.41e-48, 8.49e-109j)
| (0.14599524764363841228 - 3.4246122195441341873e-442j)  +/-  (1.46e-47, 1.93e-108j)
| (0.0046641746195996005792 + 3.4692264432169076424e-443j)  +/-  (2.34e-49, 2.71e-110j)
