Starting with polynomial:
P : 429/16*t^7 - 693/16*t^5 + 315/16*t^3 - 35/16*t
Extension levels are: 7 16
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Trying to find an order 16 Kronrod extension for:
P1 : 429/16*t^7 - 693/16*t^5 + 315/16*t^3 - 35/16*t
Solvable: 1
-------------------------------------------------
Ending with final polynomial:
P : 429/16*t^23 - 814453542657469/5190588893712*t^21 + 332613072544398149/832224419291824*t^19 - 60434669839704081761/104028052411478000*t^17 + 911288943452960320423/1716462864789387000*t^15 - 2788451867710786781/8802373665586600*t^13 + 99305037719399449/800215787780600*t^11 - 3919384318228123579/125313792366441960*t^9 + 9825341915024369299/2036020735513470000*t^7 - 44745439665748799999/107909098982213910000*t^5 + 1067710391708808827/64745459389328346000*t^3 - 4195757732088601/21581819796442782000*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
-------------------------------------------------
The nodes are:
| (0.99799364786185484161 + 1.2056524547344221593e-329j)  +/-  (3.08e-120, 3.08e-120j)
| (0.1388704900512106627 + 7.0272569578174948603e-339j)  +/-  (8.86e-127, 8.86e-127j)
| (-0.94910791234275852453 - 2.4949017023726268802e-339j)  +/-  (4.73e-120, 4.73e-120j)
| (0.52875559147107004702 + 1.9741258825589198857e-343j)  +/-  (3.55e-123, 3.55e-123j)
| (0.94910791234275852453 - 3.0418554040911823938e-349j)  +/-  (4.84e-120, 4.84e-120j)
| (0.40584515137739716691 + 1.2874805285450725685e-360j)  +/-  (2.74e-124, 2.74e-124j)
| (-0.98287596570383387832 + 1.4910715005370807725e-352j)  +/-  (6.36e-120, 6.36e-120j)
| (-0.89690728630508935865 - 1.1997540231311580771e-355j)  +/-  (2.47e-120, 2.47e-120j)
| (-0.74153118559939443986 + 1.8640038791634958264e-359j)  +/-  (1.78e-121, 1.78e-121j)
| (-0.99799364786185484161 + 5.4322860788564448886e-356j)  +/-  (3.55e-120, 3.55e-120j)
| (0.82726326692374895567 - 1.2616288247185237343e-355j)  +/-  (8.13e-121, 8.13e-121j)
| (-0.40584515137739716691 + 5.9712287197354756279e-364j)  +/-  (2.65e-124, 2.65e-124j)
| (-0.6413798687646698755 - 8.1783963512714054112e-362j)  +/-  (2.94e-122, 2.94e-122j)
| (-0.52875559147107004702 + 1.8601614618545994226e-364j)  +/-  (3.57e-123, 3.57e-123j)
| (7.5296120116836853301e-370 - 3.5987504620906635296e-371j)  +/-  (1.73e-368, 1.73e-368j)
| (0.74153118559939443986 + 1.0874189686320422242e-358j)  +/-  (1.91e-121, 1.91e-121j)
| (0.89690728630508935865 + 1.3630461810033735772e-364j)  +/-  (2.52e-120, 2.52e-120j)
| (0.98287596570383387832 - 1.458520224000820016e-383j)  +/-  (6.24e-120, 6.24e-120j)
| (-0.82726326692374895567 + 1.6766706308788639242e-395j)  +/-  (8.39e-121, 8.39e-121j)
| (-0.2750357124712873529 - 4.5777269351579114226e-401j)  +/-  (1.54e-125, 1.54e-125j)
| (0.2750357124712873529 - 8.8949211801206186397e-402j)  +/-  (1.61e-125, 1.61e-125j)
| (0.6413798687646698755 + 8.0061838931776726096e-402j)  +/-  (3.15e-122, 3.15e-122j)
| (-0.1388704900512106627 + 1.4652004386535752337e-410j)  +/-  (1.07e-126, 1.07e-126j)
-------------------------------------------------
The weights are:
| (0.006531210630826968939 - 9.7042211008423219926e-330j)  +/-  (9.41e-40, 1.91e-97j)
| (0.13796597427820947537 - 5.952503809554582173e-331j)  +/-  (3.85e-40, 7.82e-98j)
| (0.043113903691341972167 - 1.435556611616335407e-331j)  +/-  (1.01e-40, 2.05e-98j)
| (0.11814992531771326251 + 1.0073578508372860642e-330j)  +/-  (1.84e-40, 3.74e-98j)
| (0.043113903691341972167 - 5.717771202530127032e-330j)  +/-  (4.53e-41, 9.21e-99j)
| (0.12727235643820903391 - 8.290724549548700186e-331j)  +/-  (1.85e-40, 3.76e-98j)
| (0.024344081856459838497 + 1.0227478849915380764e-331j)  +/-  (1.81e-41, 3.67e-99j)
| (0.061120167412052582662 + 1.7748954353010819917e-331j)  +/-  (1.37e-41, 2.78e-99j)
| (0.09324414685631693478 + 2.4067229040612070186e-331j)  +/-  (2.29e-42, 4.65e-100j)
| (0.006531210630826968939 - 3.9451002763395358056e-332j)  +/-  (5.73e-42, 1.16e-99j)
| (0.077941294515931098158 - 2.2354475587811527019e-330j)  +/-  (2.59e-43, 5.26e-101j)
| (0.12727235643820903391 - 3.4970825198235309983e-331j)  +/-  (2.9e-43, 5.9e-101j)
| (0.10673349592580238882 - 2.7373099140753692024e-331j)  +/-  (4.48e-43, 9.11e-101j)
| (0.11814992531771326251 + 3.0960594678546600366e-331j)  +/-  (2.3e-43, 4.68e-101j)
| (0.1393232098501692828 + 5.1495472306001627597e-331j)  +/-  (3.82e-44, 7.76e-102j)
| (0.09324414685631693478 + 1.6324237822663751405e-330j)  +/-  (6.87e-45, 1.4e-102j)
| (0.061120167412052582662 + 3.3271065524362558635e-330j)  +/-  (3.33e-45, 6.77e-103j)
| (0.024344081856459838497 + 1.3401063902723117388e-329j)  +/-  (2.56e-45, 5.2e-103j)
| (0.077941294515931098158 - 2.0909868299561926975e-331j)  +/-  (7.54e-45, 1.51e-102j)
| (0.13392183815205180278 + 3.9572516076882904141e-331j)  +/-  (5.17e-46, 1.04e-103j)
| (0.13392183815205180278 + 6.9681749844704421088e-331j)  +/-  (4.35e-46, 9.04e-104j)
| (0.10673349592580238882 - 1.2583566901343207065e-330j)  +/-  (3.67e-46, 7.82e-104j)
| (0.13796597427820947537 - 4.4982806125098383902e-331j)  +/-  (3.26e-46, 6.41e-104j)
