Starting with polynomial:
P : t^7 - 21*t^5 + 105*t^3 - 105*t
Extension levels are: 7 14
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Trying to find an order 14 Kronrod extension for:
P1 : t^7 - 21*t^5 + 105*t^3 - 105*t
Solvable: 1
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Ending with final polynomial:
P : t^21 - 1757/10*t^19 + 372883/30*t^17 - 9208843/20*t^15 + 38960831/4*t^13 - 482270789/4*t^11 + 3448558113/4*t^9 - 13584319749/4*t^7 + 26812306521/4*t^5 - 22041464445/4*t^3 + 4851751905/4*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
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The nodes are:
| (-6.2563577326427727983 + 8.474615913072580645e-357j)  +/-  (5.93e-123, 5.93e-123j)
| (3.0363167104208632606 - 1.1555875760051916734e-362j)  +/-  (1.9e-123, 1.9e-123j)
| (-5.337965697641837342 + 7.7195177533418131463e-366j)  +/-  (1.02e-122, 1.02e-122j)
| (7.3556578365158105709 + 9.7224167332062143571e-369j)  +/-  (1.32e-123, 1.32e-123j)
| (-7.3556578365158105709 - 2.5997761571382419316e-374j)  +/-  (1.44e-123, 1.44e-123j)
| (5.337965697641837342 - 9.3821364487807996914e-378j)  +/-  (9.91e-123, 9.91e-123j)
| (3.7504397177257422563 - 1.8560485014523955189e-387j)  +/-  (5.74e-123, 5.74e-123j)
| (-1.7420067727798882962 + 1.4708603528460583121e-393j)  +/-  (1.22e-124, 1.22e-124j)
| (-3.7504397177257422563 - 2.0222931695404360671e-392j)  +/-  (5.23e-123, 5.23e-123j)
| (-4.5131658785759243918 + 3.2018323797528579695e-397j)  +/-  (9.7e-123, 9.7e-123j)
| (0.57959892526612873838 - 5.0881997772591726127e-399j)  +/-  (1.61e-126, 1.61e-126j)
| (6.2563577326427727983 + 4.6612344456721709532e-404j)  +/-  (6.43e-123, 6.43e-123j)
| (3.8045136071217811578e-416 + 3.766024364403817613e-415j)  +/-  (7.95e-414, 7.95e-414j)
| (-2.3667594107345412886 - 2.2169803805547001797e-414j)  +/-  (6.06e-124, 6.06e-124j)
| (4.5131658785759243918 - 1.2074149458399621622e-417j)  +/-  (1.09e-122, 1.09e-122j)
| (1.1544053947399681272 + 2.2809022304171728005e-423j)  +/-  (1.8e-125, 1.8e-125j)
| (1.7420067727798882962 + 2.3153142950153429123e-422j)  +/-  (1.23e-124, 1.23e-124j)
| (-3.0363167104208632606 - 1.1700807851882415889e-420j)  +/-  (1.87e-123, 1.87e-123j)
| (-1.1544053947399681272 + 7.2706515971518390235e-423j)  +/-  (1.51e-125, 1.51e-125j)
| (-0.57959892526612873838 + 1.1691278357070614935e-423j)  +/-  (1.61e-126, 1.61e-126j)
| (2.3667594107345412886 + 2.703521952042235728e-427j)  +/-  (5.06e-124, 5.06e-124j)
-------------------------------------------------
The weights are:
| (1.2438118603265630208e-09 + 3.726561836476373162e-365j)  +/-  (5.92e-51, 5.73e-112j)
| (0.0027474591190104329973 + 8.8277683547897756557e-363j)  +/-  (1.1e-45, 1.06e-106j)
| (2.2389116381951573299e-07 - 2.2893327050754057861e-364j)  +/-  (7.51e-50, 7.27e-111j)
| (8.9857923030471386195e-13 - 1.3661597179572817411e-368j)  +/-  (9.93e-54, 9.6e-115j)
| (8.9857923030471386195e-13 + 1.6936509033643248337e-367j)  +/-  (6.63e-53, 6.41e-114j)
| (2.2389116381951573299e-07 - 1.8097511965177448999e-365j)  +/-  (3.3e-51, 3.19e-112j)
| (0.00025947386068715770253 - 1.6095713347581665654e-363j)  +/-  (1.41e-48, 1.36e-109j)
| (0.052787547252404605877 + 1.8356923663531653835e-361j)  +/-  (3.43e-45, 3.32e-106j)
| (0.00025947386068715770253 - 6.463701069484510073e-363j)  +/-  (1.78e-49, 1.73e-110j)
| (1.1906924634301593617e-05 + 1.3129383487438701606e-363j)  +/-  (3.03e-50, 2.93e-111j)
| (0.19440564429208587453 + 3.5280152487195380054e-361j)  +/-  (3.03e-46, 2.95e-107j)
| (1.2438118603265630208e-09 + 8.4113243974771620118e-367j)  +/-  (2.02e-53, 1.94e-114j)
| (0.23197318701315581799 - 4.3402947174028843308e-361j)  +/-  (1.54e-46, 1.51e-107j)
| (0.015686830506679761153 - 7.7745304433869445409e-362j)  +/-  (2.54e-48, 2.46e-109j)
| (1.1906924634301593617e-05 + 2.1189312559331600781e-364j)  +/-  (3.61e-51, 3.47e-112j)
| (0.11811431940204569808 - 2.2243132750039223404e-361j)  +/-  (1.59e-47, 1.55e-108j)
| (0.052787547252404605877 + 1.038196546614167731e-361j)  +/-  (9.11e-49, 9e-110j)
| (0.0027474591190104329973 + 2.5283517379118992001e-362j)  +/-  (3.91e-50, 4.21e-111j)
| (0.11811431940204569808 - 3.2274692335393674163e-361j)  +/-  (1.5e-48, 1.6e-109j)
| (0.19440564429208587453 + 4.2464309819616524016e-361j)  +/-  (1.92e-48, 2.08e-109j)
| (0.015686830506679761153 - 3.5234563812193725458e-362j)  +/-  (1.04e-49, 9.24e-111j)
