Starting with polynomial:
P : 256*t^8 - 3584*t^6 + 13440*t^4 - 13440*t^2 + 1680
Extension levels are: 8 16
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Trying to find an order 16 Kronrod extension for:
P1 : 256*t^8 - 3584*t^6 + 13440*t^4 - 13440*t^2 + 1680
Solvable: 1
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Ending with final polynomial:
P : 256*t^24 - 5424530944/205799*t^22 + 1144816116864/1028995*t^20 - 25882957659776/1028995*t^18 + 68809147521296/205799*t^16 - 556247611045056/205799*t^14 + 2738586270109872/205799*t^12 - 728436514142064/18709*t^10 + 1200200825947851/18709*t^8 - 1009122581859210/18709*t^6 + 719728821634095/37418*t^4 - 72802386399015/37418*t^2 + 4752962138925/299344
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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
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The nodes are:
| (-2.9306374202572440192 + 7.7284644723451491849e-445j)  +/-  (2.03e-122, 2.03e-122j)
| (-2.4371414646509903823 + 5.0464335926516400099e-455j)  +/-  (8.87e-123, 8.87e-123j)
| (-4.0398498657499472277 + 3.9932582566879564396e-461j)  +/-  (1.98e-122, 1.98e-122j)
| (5.4550494655798408359 - 2.6082183469387905418e-464j)  +/-  (2.35e-123, 2.35e-123j)
| (3.4624517242477418427 - 2.9004400918288259093e-463j)  +/-  (2.24e-122, 2.24e-122j)
| (4.0398498657499472277 - 2.461854249411545791e-463j)  +/-  (2.11e-122, 2.11e-122j)
| (2.9306374202572440192 + 2.7459094853997582464e-465j)  +/-  (1.77e-122, 1.77e-122j)
| (-4.6838025434930521539 + 5.0462639982383660587e-468j)  +/-  (1.12e-122, 1.12e-122j)
| (4.6838025434930521539 - 1.7643570430287855295e-469j)  +/-  (1.12e-122, 1.12e-122j)
| (1.9816567566958429259 + 1.2986595174639470385e-468j)  +/-  (3.32e-123, 3.32e-123j)
| (2.4371414646509903823 + 1.0683290869822853285e-472j)  +/-  (9.1e-123, 9.1e-123j)
| (1.1571937124467801947 - 1.9161531637375426698e-476j)  +/-  (1.73e-124, 1.73e-124j)
| (-5.4550494655798408359 + 1.4908658874658714849e-479j)  +/-  (2.47e-123, 2.47e-123j)
| (-1.5610430277744906744 - 2.3996067375895888072e-486j)  +/-  (9.28e-124, 9.28e-124j)
| (1.5610430277744906744 - 9.0434030886245668641e-496j)  +/-  (9.22e-124, 9.22e-124j)
| (0.75663726884915739543 + 5.4387609066580293406e-497j)  +/-  (2.59e-125, 2.59e-125j)
| (0.0944958405478889504 + 1.1785802687828246078e-495j)  +/-  (2.81e-127, 2.81e-127j)
| (-1.9816567566958429259 - 4.708390718905961125e-496j)  +/-  (3.73e-123, 3.73e-123j)
| (-0.75663726884915739543 - 3.6203463499503378878e-503j)  +/-  (2.33e-125, 2.33e-125j)
| (-0.0944958405478889504 + 4.2417213144330783063e-504j)  +/-  (1.95e-127, 1.95e-127j)
| (-3.4624517242477418427 + 1.3305610017905866687e-502j)  +/-  (2.32e-122, 2.32e-122j)
| (0.38118699020732211685 - 4.1167439023216573848e-512j)  +/-  (2.3e-126, 2.3e-126j)
| (-0.38118699020732211685 + 3.1270620348948347003e-511j)  +/-  (2.3e-126, 2.3e-126j)
| (-1.1571937124467801947 - 3.6385362773044951633e-512j)  +/-  (1.91e-124, 1.91e-124j)
-------------------------------------------------
The weights are:
| (5.3810379202921402683e-05 + 1.7934241393440273551e-448j)  +/-  (2.93e-41, 8.5e-102j)
| (0.00070516698166672389323 - 6.3492666055842415639e-448j)  +/-  (1.26e-39, 3.67e-100j)
| (2.7902612907106336337e-08 - 2.298762999592923545e-451j)  +/-  (6.61e-45, 1.92e-105j)
| (5.9642960835155418045e-14 - 1.3040457914452148123e-455j)  +/-  (1.75e-49, 5.08e-110j)
| (1.9374817663969774365e-06 + 6.2528064477907391862e-451j)  +/-  (1.26e-45, 3.66e-106j)
| (2.7902612907106336337e-08 - 3.6580176157755439974e-452j)  +/-  (4.53e-47, 1.32e-107j)
| (5.3810379202921402683e-05 - 7.0952414820582059667e-450j)  +/-  (6.11e-45, 1.78e-105j)
| (1.156877691419869765e-10 + 5.1136848398461763507e-453j)  +/-  (6.87e-50, 2e-110j)
| (1.156877691419869765e-10 + 1.1773858556668225273e-453j)  +/-  (1.04e-48, 3.02e-109j)
| (0.0048516096080187532486 - 3.558442248498773551e-448j)  +/-  (9.86e-44, 2.87e-104j)
| (0.00070516698166672389323 + 5.8373071216589495603e-449j)  +/-  (1.48e-44, 4.29e-105j)
| (0.059498414095787973649 - 5.6822223038062134571e-447j)  +/-  (1.11e-42, 3.24e-103j)
| (5.9642960835155418045e-14 - 4.3318283607446855776e-455j)  +/-  (1.05e-52, 3.04e-113j)
| (0.020136912292261491039 - 5.2424818146730222146e-447j)  +/-  (1.14e-44, 3.29e-105j)
| (0.020136912292261491039 + 1.5985272726990160498e-447j)  +/-  (2.06e-43, 6.03e-104j)
| (0.12575476830343217314 + 1.8642393219335202855e-446j)  +/-  (4.94e-43, 1.44e-103j)
| (0.12068444753246710567 + 1.6056850278189909374e-445j)  +/-  (5.58e-43, 1.66e-103j)
| (0.0048516096080187532486 + 1.8419885468260831137e-447j)  +/-  (9.92e-46, 2.85e-106j)
| (0.12575476830343217314 - 3.1618960383427297188e-446j)  +/-  (5.04e-44, 1.51e-104j)
| (0.12068444753246710567 - 1.7126828994627101245e-445j)  +/-  (2e-43, 5.9e-104j)
| (1.9374817663969774365e-06 + 7.5166742839885951757e-450j)  +/-  (5.37e-49, 1.53e-109j)
| (0.16831290530703614177 - 6.2919634960715196357e-446j)  +/-  (1e-43, 2.9e-104j)
| (0.16831290530703614177 + 8.1734785074757983662e-446j)  +/-  (3.18e-44, 1.04e-104j)
| (0.059498414095787973649 + 1.3097661421950125122e-446j)  +/-  (3.67e-45, 8.86e-106j)
