Starting with polynomial:
P : t^2 - 1
Extension levels are: 2 9
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Trying to find an order 9 Kronrod extension for:
P1 : t^2 - 1
Solvable: 1
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Ending with final polynomial:
P : t^11 - 619/7*t^9 + 15354/7*t^7 - 19566*t^5 + 59445*t^3 - 41985*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
Positive weights:   11 out of 11
Indefinite weights: 0 out of 11
Negative weights:   0 out of 11
Extension rule has valid weights: 1
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The nodes are:
| (-4.3862249342620953383 + 2.1706628412940209799e-164j)  +/-  (2.73e-61, 2.73e-61j)
| (-7.3693356610308432189 + 6.8893107755913751804e-166j)  +/-  (1.04e-61, 1.04e-61j)
| (-3.1255538604259774764 + 2.1706628412940209799e-165j)  +/-  (2.04e-61, 2.04e-61j)
| (7.3693356610308432189 + 5.4266571032350524498e-166j)  +/-  (1.04e-61, 1.04e-61j)
| (-1 + 5.4266571032350524498e-166j)  +/-  (1.19e-62, 1.19e-62j)
| (-2.0281536517888087075 - 2.3063292688748972912e-165j)  +/-  (5.12e-62, 5.12e-62j)
| (2.9846614067792788474e-165 + 1.5194639889058146859e-164j)  +/-  (1.7e-163, 1.7e-163j)
| (1 + 1.2938158758247023701e-172j)  +/-  (1.19e-62, 1.19e-62j)
| (2.0281536517888087075 - 1.4364241749661470161e-187j)  +/-  (5.32e-62, 5.32e-62j)
| (3.1255538604259774764 + 3.9868779804390270142e-205j)  +/-  (1.78e-61, 1.78e-61j)
| (4.3862249342620953383 - 2.7664523314090326654e-222j)  +/-  (2.63e-61, 2.63e-61j)
-------------------------------------------------
The weights are:
| (3.7562663476214825589e-05 - 1.1767976407991520247e-167j)  +/-  (6.68e-25, 9.08e-56j)
| (2.0089467298375307743e-10 + 6.8215579776098110987e-170j)  +/-  (2.14e-27, 2.91e-58j)
| (0.0034823539991797408242 + 1.6560932271169407711e-166j)  +/-  (7.3e-24, 9.93e-55j)
| (2.0089467298375307743e-10 - 7.0595883958865245399e-170j)  +/-  (1.08e-28, 1.47e-59j)
| (0.24411771037392633414 + 5.098115924679482123e-165j)  +/-  (3.48e-22, 4.73e-53j)
| (0.05376083139570835851 - 1.2093743167809858807e-165j)  +/-  (3.11e-23, 4.23e-54j)
| (0.39720308273362935742 - 3.3558710209798799713e-166j)  +/-  (2.14e-22, 2.91e-53j)
| (0.24411771037392633414 - 4.6178861925875570838e-165j)  +/-  (1.04e-22, 1.42e-53j)
| (0.05376083139570835851 + 1.0829516243604256814e-165j)  +/-  (7.5e-25, 1.02e-55j)
| (0.0034823539991797408242 - 1.8744969840484569235e-166j)  +/-  (3.34e-26, 4.53e-57j)
| (3.7562663476214825589e-05 + 1.5390794831949059807e-167j)  +/-  (2.27e-27, 3.08e-58j)
