Starting with polynomial:
P : 8192*t^13 - 319488*t^11 + 4392960*t^9 - 26357760*t^7 + 69189120*t^5 - 69189120*t^3 + 17297280*t
Extension levels are: 13 20
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Trying to find an order 20 Kronrod extension for:
P1 : 8192*t^13 - 319488*t^11 + 4392960*t^9 - 26357760*t^7 + 69189120*t^5 - 69189120*t^3 + 17297280*t
Solvable: 1
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Ending with final polynomial:
P : 8192*t^33 - 19545172279296/12466867*t^31 + 1628479144396800/12466867*t^29 - 78073107472373760/12466867*t^27 + 2399010881583813120/12466867*t^25 - 49825817709706183680/12466867*t^23 + 719024285033233902720/12466867*t^21 - 1042886160012159446400/1780981*t^19 + 7462751998634886074400/1780981*t^17 - 37359372760475726332800/1780981*t^15 + 128653074461500258199400/1780981*t^13 - 296331099225795679944600/1780981*t^11 + 437323559510054761508250/1780981*t^9 - 387936126362667166069500/1780981*t^7 + 377382794865165680716125/3561962*t^5 - 88380880665300855757125/3561962*t^3 + 14942089480824877746375/7123924*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:
| (4.5991916441319721219 - 2.388790529755417574e-438j)  +/-  (2.37e-120, 2.37e-120j)
| (-3.6472244055039055256 + 4.1718947227283563428e-442j)  +/-  (3.65e-120, 3.65e-120j)
| (5.752793521942928346 + 1.7972978841967781704e-444j)  +/-  (3.28e-121, 3.28e-121j)
| (-4.1013375961786396412 + 3.2315453144816448844e-445j)  +/-  (3.15e-120, 3.15e-120j)
| (-5.14335958666687487 + 1.0052899431249479031e-449j)  +/-  (1.1e-120, 1.1e-120j)
| (3.2466089783724099881 + 3.8421787551541370825e-454j)  +/-  (3.6e-120, 3.6e-120j)
| (-6.4855184048527327108 + 1.5363043561941560021e-467j)  +/-  (4.28e-122, 4.28e-122j)
| (-5.752793521942928346 - 3.957134558082589767e-467j)  +/-  (3.43e-121, 3.43e-121j)
| (6.4855184048527327108 + 1.9861044114058918734e-465j)  +/-  (5.08e-122, 5.08e-122j)
| (2.8885900367424354766 - 3.0568554382561774228e-468j)  +/-  (1.86e-120, 1.86e-120j)
| (2.5197356856782378834 - 1.0296746696973989716e-474j)  +/-  (8.79e-121, 8.79e-121j)
| (1.2200550365907484262 + 5.9587597544042427712e-483j)  +/-  (2.11e-123, 2.11e-123j)
| (-1.5995441138456123141 - 1.0485729131548130512e-482j)  +/-  (2.71e-122, 2.71e-122j)
| (-2.5197356856782378834 + 1.1986180971226674702e-479j)  +/-  (9.19e-121, 9.19e-121j)
| (5.14335958666687487 - 8.2840593485231351247e-479j)  +/-  (1.1e-120, 1.1e-120j)
| (2.1417394430849442651 - 1.3077814894315654086e-481j)  +/-  (3.44e-121, 3.44e-121j)
| (-4.5991916441319721219 - 3.0618955160394688492e-483j)  +/-  (2.34e-120, 2.34e-120j)
| (-2.8885900367424354766 - 1.1038405482899826018e-482j)  +/-  (1.92e-120, 1.92e-120j)
| (-0.7967069070324384949 + 4.9804197296608790291e-490j)  +/-  (2.67e-124, 2.67e-124j)
| (-1.2200550365907484262 - 2.0791747623969985665e-489j)  +/-  (2.14e-123, 2.14e-123j)
| (3.6472244055039055256 + 7.7323850035039235069e-486j)  +/-  (3.67e-120, 3.67e-120j)
| (0.43390575349217526076 - 5.8377991872744934557e-501j)  +/-  (1.53e-125, 1.53e-125j)
| (4.1013375961786396412 + 4.6428934457922440034e-495j)  +/-  (3.51e-120, 3.51e-120j)
| (-2.1417394430849442651 + 3.0239013955396254814e-498j)  +/-  (3.54e-121, 3.54e-121j)
| (-0.60576387917106011308 + 5.2328515908647548273e-503j)  +/-  (8.35e-125, 8.35e-125j)
| (1.1063749237489454222e-511 + 1.581203907937182041e-511j)  +/-  (6.37e-510, 6.37e-510j)
| (0.7967069070324384949 + 2.0006552982565359637e-502j)  +/-  (2.8e-124, 2.8e-124j)
| (1.853107651601512142 - 9.4793392605643145137e-500j)  +/-  (1.21e-121, 1.21e-121j)
| (-1.853107651601512142 - 2.4965580998138521205e-500j)  +/-  (1.24e-121, 1.24e-121j)
| (-0.43390575349217526076 + 1.5208212936863947012e-505j)  +/-  (1.43e-125, 1.43e-125j)
| (-3.2466089783724099881 + 1.5900030721267069209e-502j)  +/-  (3.03e-120, 3.03e-120j)
| (1.5995441138456123141 + 2.8858064932178169467e-505j)  +/-  (3.26e-122, 3.26e-122j)
| (0.60576387917106011308 - 4.0829671967958075036e-508j)  +/-  (8.64e-125, 8.64e-125j)
-------------------------------------------------
The weights are:
| (1.907572367415695756e-10 + 2.8476139184508121771e-447j)  +/-  (5.49e-40, 5.85e-99j)
| (4.048070979590063466e-07 + 1.7541903801801001629e-446j)  +/-  (2.98e-37, 3.17e-96j)
| (1.5663854503288022981e-15 - 2.2488817826339394683e-451j)  +/-  (1.49e-43, 1.58e-102j)
| (1.3318928676855438127e-08 - 1.0475562037699763862e-447j)  +/-  (4.79e-39, 5.1e-98j)
| (1.0467078277594918417e-12 - 1.5045033298017742736e-450j)  +/-  (1.03e-42, 1.09e-101j)
| (5.5527703476890356826e-06 - 9.6126911274344337226e-445j)  +/-  (2.25e-38, 2.4e-97j)
| (2.5729089667509090803e-19 - 1.3213798625928858243e-454j)  +/-  (9.43e-47, 1e-105j)
| (1.5663854503288022981e-15 + 2.4912284095734676352e-452j)  +/-  (1.06e-44, 1.13e-103j)
| (2.5729089667509090803e-19 + 7.8008121330608808124e-454j)  +/-  (7.47e-48, 7.95e-107j)
| (4.7766217722966177934e-05 + 4.4878462997069824692e-444j)  +/-  (1.8e-38, 1.91e-97j)
| (0.00037574375747553450363 - 1.8403258845398667991e-443j)  +/-  (1.49e-37, 1.58e-96j)
| (0.051572619933929426301 - 6.0346068085701203086e-442j)  +/-  (2.78e-32, 2.96e-91j)
| (0.01458036929039109001 + 1.9421631112959408638e-442j)  +/-  (3.94e-35, 4.19e-94j)
| (0.00037574375747553450363 - 5.4154024852318864507e-444j)  +/-  (3.85e-39, 4.1e-98j)
| (1.0467078277594918417e-12 + 2.7152796687357548483e-449j)  +/-  (1.94e-45, 2.06e-104j)
| (0.0020667481504410860898 + 8.599786738900384534e-443j)  +/-  (1.41e-37, 1.5e-96j)
| (1.907572367415695756e-10 + 4.8946610607959443557e-449j)  +/-  (2.8e-44, 2.98e-103j)
| (4.7766217722966177934e-05 + 1.0374533295568366969e-444j)  +/-  (1.25e-40, 1.33e-99j)
| (0.14031817967027194208 + 1.7703429896429339952e-441j)  +/-  (1.21e-35, 1.28e-94j)
| (0.051572619933929426301 - 3.5115763380305687939e-442j)  +/-  (4.65e-36, 4.95e-95j)
| (4.048070979590063466e-07 + 1.4325870126134911768e-445j)  +/-  (1.86e-42, 1.98e-101j)
| (0.22626350997031161982 + 3.5397345721739295964e-441j)  +/-  (3.57e-37, 3.79e-96j)
| (1.3318928676855438127e-08 - 1.8754099522140374614e-446j)  +/-  (1.17e-43, 1.25e-102j)
| (0.0020667481504410860898 + 3.1508358527220455439e-443j)  +/-  (3.67e-40, 3.92e-99j)
| (-0.058445295062451845728 - 3.7765638828605902317e-441j)  +/-  (5.38e-37, 5.71e-96j)
| (0.23863589918532372952 - 1.4250441324711088002e-441j)  +/-  (1.74e-37, 1.84e-96j)
| (0.14031817967027194208 + 2.5089781579106138815e-441j)  +/-  (2.74e-38, 2.87e-97j)
| (0.0038964373910664798781 - 2.5867355628072655965e-442j)  +/-  (6.91e-40, 7.19e-99j)
| (0.0038964373910664798781 - 1.1051279279449093848e-442j)  +/-  (9.57e-40, 1.03e-98j)
| (0.22626350997031161982 + 2.9313869205341724442e-441j)  +/-  (2.42e-38, 2.77e-97j)
| (5.5527703476890356826e-06 - 1.6969644732540503818e-445j)  +/-  (7.44e-43, 7.96e-102j)
| (0.01458036929039109001 + 4.0013002759095083073e-442j)  +/-  (4.71e-40, 4.54e-99j)
| (-0.058445295062451845728 - 4.9176021195288298164e-441j)  +/-  (1.17e-38, 1.4e-97j)
