Starting with polynomial:
P : t^4 - 6*t^2 + 3
Extension levels are: 4 20
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Trying to find an order 20 Kronrod extension for:
P1 : t^4 - 6*t^2 + 3
Solvable: 1
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Ending with final polynomial:
P : t^24 - 84138653676/363937411*t^22 + 32020783562037/1455749644*t^20 - 818664521682555/727874822*t^18 + 2902354334703135/85632332*t^16 - 13308321713911110/21408083*t^14 + 296858052476011845/42816166*t^12 - 979371031782448305/21408083*t^10 + 7231298316318101025/42816166*t^8 - 6819868970176912650/21408083*t^6 + 23115246943434671025/85632332*t^4 - 3840059178024144075/42816166*t^2 + 36936160291505475/5037196
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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:
| (5.244713429373169514 - 1.3933045257181907766e-433j)  +/-  (5e-122, 5e-122j)
| (-8.0720954824796596598 - 1.4952553798201365261e-440j)  +/-  (4.28e-123, 4.28e-123j)
| (6.9837383000327542002 - 9.2941171247783687642e-440j)  +/-  (2.3e-122, 2.3e-122j)
| (-3.0269747476859080056 - 2.6510887450784148056e-440j)  +/-  (5.6e-123, 5.6e-123j)
| (8.0720954824796596598 + 2.908238230744219475e-442j)  +/-  (4.58e-123, 4.58e-123j)
| (-6.0704863650986940061 - 4.4143995039296468241e-440j)  +/-  (4.65e-122, 4.65e-122j)
| (3.7371891405471332409 - 2.2086825707995778661e-442j)  +/-  (1.59e-122, 1.59e-122j)
| (-5.244713429373169514 - 1.4355114766742633176e-445j)  +/-  (5.57e-122, 5.57e-122j)
| (-6.9837383000327542002 + 3.4241242188409437371e-449j)  +/-  (2.3e-122, 2.3e-122j)
| (2.3344142183389772393 + 6.3703393434410771545e-452j)  +/-  (1.12e-123, 1.12e-123j)
| (0.95727802229468898435 - 6.9673955178716743132e-458j)  +/-  (4.28e-125, 4.28e-125j)
| (4.4728052752859291175 - 4.7541489837638474901e-462j)  +/-  (3.26e-122, 3.26e-122j)
| (3.0269747476859080056 - 1.3395384578497529064e-472j)  +/-  (4.87e-123, 4.87e-123j)
| (-0.95727802229468898435 + 5.4985765365665662549e-478j)  +/-  (4.4e-125, 4.4e-125j)
| (-4.4728052752859291175 - 3.477304817196586447e-481j)  +/-  (3.4e-122, 3.4e-122j)
| (6.0704863650986940061 - 2.5176456154127629489e-490j)  +/-  (4.43e-122, 4.43e-122j)
| (1.6525104836673741412 - 1.3452544911159888929e-496j)  +/-  (2.2e-124, 2.2e-124j)
| (-0.34413999107627035477 - 1.0272049999684786853e-499j)  +/-  (1.5e-126, 1.5e-126j)
| (-0.74196378430272585765 + 1.2314267655408468512e-498j)  +/-  (2.58e-125, 2.58e-125j)
| (0.74196378430272585765 + 8.0957165576150723686e-499j)  +/-  (2.46e-125, 2.46e-125j)
| (-3.7371891405471332409 - 4.3794900414086355343e-498j)  +/-  (1.78e-122, 1.78e-122j)
| (-2.3344142183389772393 - 1.2582880238857199029e-500j)  +/-  (1.03e-123, 1.03e-123j)
| (0.34413999107627035477 + 2.516196525338043162e-504j)  +/-  (1.57e-126, 1.57e-126j)
| (-1.6525104836673741412 + 8.1113618118106234279e-504j)  +/-  (2e-124, 2e-124j)
-------------------------------------------------
The weights are:
| (3.3747250076880230343e-07 + 1.4158970402453763844e-439j)  +/-  (4.78e-47, 3.36e-107j)
| (3.5350881715179982843e-15 + 1.5083315655513429529e-445j)  +/-  (4.79e-52, 3.36e-112j)
| (9.9999979126614099208e-12 - 8.2298143922542033982e-443j)  +/-  (3.03e-50, 2.13e-110j)
| (0.0028611048233905567846 + 1.6361692441627276354e-438j)  +/-  (8.92e-44, 6.27e-104j)
| (3.5350881715179982843e-15 + 7.1040591259450909635e-445j)  +/-  (6.3e-52, 4.42e-112j)
| (3.4213460692440502258e-09 + 3.1076271067619109167e-442j)  +/-  (4.14e-50, 2.91e-110j)
| (0.00026687358899148301964 + 1.7613260645794224586e-438j)  +/-  (1.23e-46, 8.66e-107j)
| (3.3747250076880230343e-07 - 4.4827442912635498003e-441j)  +/-  (2.86e-49, 2.01e-109j)
| (9.9999979126614099208e-12 - 1.1703930464359336193e-443j)  +/-  (1.91e-51, 1.34e-111j)
| (0.017941977125724029889 + 2.0448480361370646274e-437j)  +/-  (5.19e-45, 3.64e-105j)
| (0.19640972122288612251 + 6.2010256889750343611e-436j)  +/-  (3.93e-44, 2.78e-104j)
| (1.3571450378508717398e-05 - 5.3510265790756925381e-439j)  +/-  (1.49e-48, 1.05e-108j)
| (0.0028611048233905567846 - 6.1031743634070944608e-438j)  +/-  (1.43e-46, 1e-106j)
| (0.19640972122288612251 - 4.2867215101921876323e-436j)  +/-  (1.29e-44, 9.16e-105j)
| (1.3571450378508717398e-05 + 4.2507334250481994534e-440j)  +/-  (6.84e-50, 4.8e-110j)
| (3.4213460692440502258e-09 + 4.258163720121454181e-441j)  +/-  (4.24e-51, 2.98e-111j)
| (0.069222026146138035544 - 7.2898860413586299929e-437j)  +/-  (1.57e-45, 1.11e-105j)
| (0.26483704757407903823 - 5.0361109242061789695e-436j)  +/-  (9.4e-45, 6.64e-105j)
| (-0.051552662835438145738 + 7.1752680037974450118e-436j)  +/-  (5.53e-45, 3.9e-105j)
| (-0.051552662835438145738 - 9.5400279705463889373e-436j)  +/-  (4.62e-45, 3.29e-105j)
| (0.00026687358899148301964 - 2.9564257005359059867e-439j)  +/-  (2.18e-49, 1.52e-109j)
| (0.017941977125724029889 - 7.8515265973827609939e-438j)  +/-  (2.96e-48, 2.09e-108j)
| (0.26483704757407903823 + 5.7434473144289868646e-436j)  +/-  (2.15e-46, 1.96e-106j)
| (0.069222026146138035544 + 3.7966180626974213055e-437j)  +/-  (1.59e-47, 1.07e-107j)
