Starting with polynomial:
P : 64*t^6 - 480*t^4 + 720*t^2 - 120
Extension levels are: 6 9
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Trying to find an order 9 Kronrod extension for:
P1 : 64*t^6 - 480*t^4 + 720*t^2 - 120
Solvable: 1
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Ending with final polynomial:
P : 64*t^15 - 443040/191*t^13 + 5766480/191*t^11 - 34180440/191*t^9 + 97309620/191*t^7 - 129077550/191*t^5 + 68923575/191*t^3 - 18129825/382*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: 1
  current precision for roots: 106
  current precision for roots: 212
 current precision for weights: 106
Linear system for weights solvable: 1
Sufficient bits for target precision reached
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The nodes are:
| (3.9268135162497144207 - 2.6596069198130785836e-147j)  +/-  (4.33e-61, 4.33e-61j)
| (-3.0701613138889128067 + 3.4426994361186095043e-146j)  +/-  (1.28e-60, 1.28e-60j)
| (3.0701613138889128067 + 1.5804040235897621316e-146j)  +/-  (1.22e-60, 1.22e-60j)
| (-2.3506049736744922228 - 1.9149563100960921989e-146j)  +/-  (1.28e-60, 1.28e-60j)
| (-3.9268135162497144207 - 2.4105825627036987567e-147j)  +/-  (4.43e-61, 4.43e-61j)
| (-1.3358490740136969497 - 1.9019789404239458782e-145j)  +/-  (5.14e-61, 5.14e-61j)
| (1.3358490740136969497 + 4.7901402179673801415e-148j)  +/-  (5.76e-61, 5.76e-61j)
| (2.3506049736744922228 - 7.9046478405552271148e-150j)  +/-  (1.24e-60, 1.24e-60j)
| (-1.7281759088743055938 - 2.3217516362596995584e-149j)  +/-  (1.04e-60, 1.04e-60j)
| (-0.95452011014285350763 - 2.5966959089746639797e-150j)  +/-  (1.16e-61, 1.16e-61j)
| (1.7281759088743055938 - 1.6315120349500452251e-155j)  +/-  (9.56e-61, 9.56e-61j)
| (-0.43607741192761650868 - 5.0026995170448139772e-166j)  +/-  (7.18e-63, 7.18e-63j)
| (0.95452011014285350763 - 6.7778996206018615811e-181j)  +/-  (1.1e-61, 1.1e-61j)
| (3.3176801669560788199e-195 - 9.4179307965204818114e-195j)  +/-  (1.5e-193, 1.5e-193j)
| (0.43607741192761650868 + 1.2770468531093758405e-205j)  +/-  (7.18e-63, 7.18e-63j)
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The weights are:
| (1.1106256598128842121e-07 - 5.754357492806382941e-152j)  +/-  (8.5e-26, 8.85e-56j)
| (3.5076530695648974756e-05 - 1.2770125405252545749e-150j)  +/-  (8.96e-25, 9.33e-55j)
| (3.5076530695648974756e-05 - 2.9716759814605971222e-151j)  +/-  (9.7e-25, 1.01e-54j)
| (0.0015157553175112424267 - 2.8467132062964674316e-149j)  +/-  (1.2e-23, 1.24e-53j)
| (1.1106256598128842121e-07 + 1.2740396898684105034e-151j)  +/-  (1.5e-26, 1.56e-56j)
| (0.026005678400867750431 - 1.3394766817069376574e-146j)  +/-  (5.05e-22, 5.25e-52j)
| (0.026005678400867750431 - 2.1818612364377245429e-147j)  +/-  (9.72e-23, 1.01e-52j)
| (0.0015157553175112424267 - 2.7697370142162104328e-149j)  +/-  (1.09e-24, 1.13e-54j)
| (0.015614589894054148587 - 2.7587462904867973623e-147j)  +/-  (2.97e-23, 3.09e-53j)
| (0.11463522019827456925 + 2.4328403466378441675e-146j)  +/-  (1.76e-22, 1.83e-52j)
| (0.015614589894054148587 + 4.8524810352576238324e-148j)  +/-  (1.02e-23, 1.06e-53j)
| (0.23036016700500592493 - 1.6173826997047133874e-146j)  +/-  (5.14e-23, 5.4e-53j)
| (0.11463522019827456925 + 4.4494012141222568736e-147j)  +/-  (2.9e-23, 3e-53j)
| (0.22366680318204946821 + 1.3801074921452892511e-146j)  +/-  (2.39e-23, 2.55e-53j)
| (0.23036016700500592493 - 8.4972575424885817739e-147j)  +/-  (1.51e-23, 1.5e-53j)
