Starting with polynomial:
P : t
Extension levels are: 1 2 28
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Trying to find an order 2 Kronrod extension for:
P1 : t
Solvable: 1
-------------------------------------------------
Trying to find an order 28 Kronrod extension for:
P2 : t^3 - 3/5*t
Solvable: 1
-------------------------------------------------
Ending with final polynomial:
P : t^31 - 41516085547333/5521069573305*t^29 + 8022287302181173/314700965678385*t^27 - 7616809238253747/147936351387275*t^25 + 21633993522978963/313625064941023*t^23 - 590696685053489/9145156267577*t^21 + 21029803724120541/484693282181581*t^19 - 10428098112492579/493696872562663*t^17 + 18365233589740313/2468484362813315*t^15 - 5677649507516733/3032709360027787*t^13 + 40821724983936221/124341083761139267*t^11 - 1306216217106361/33911204662128891*t^9 + 13036093320979857/4600620099162152879*t^7 - 2700878827797633/23003100495810764395*t^5 + 10371523186599629/4605220719261315031879*t^3 - 58317665286513/4605220719261315031879*t
-------------------------------------------------
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:
| (-0.98410630145298961652 - 2.3754995495725364114e-451j)  +/-  (1.47e-117, 1.47e-117j)
| (-0.96110402596342253767 - 6.6019266035897456466e-459j)  +/-  (1.6e-117, 1.6e-117j)
| (-0.92822406628965235102 + 3.2081606582119526699e-467j)  +/-  (1.28e-117, 1.28e-117j)
| (0.99697642616872827975 - 4.3298465269353785876e-474j)  +/-  (5.06e-118, 5.06e-118j)
| (0.88583871366480735855 - 1.1633231479316532002e-476j)  +/-  (5.81e-118, 5.81e-118j)
| (0.92822406628965235102 - 7.81138985601234916e-477j)  +/-  (1.17e-117, 1.17e-117j)
| (0.98410630145298961652 + 2.9694561402368674924e-477j)  +/-  (1.48e-117, 1.48e-117j)
| (-0.88583871366480735855 + 2.9820144635862161029e-482j)  +/-  (6.14e-118, 6.14e-118j)
| (-0.99697642616872827975 + 1.5839596024771988535e-496j)  +/-  (5.49e-118, 5.49e-118j)
| (0.96110402596342253767 + 1.9258768739166958644e-507j)  +/-  (1.61e-117, 1.61e-117j)
| (0.83443195446915219778 - 2.8431632114249610051e-509j)  +/-  (2.57e-118, 2.57e-118j)
| (0.28462177099265720081 + 9.2594054568510854558e-516j)  +/-  (2.29e-124, 2.29e-124j)
| (-0.70703197208114496909 - 2.190178675005598119e-508j)  +/-  (1.56e-119, 1.56e-119j)
| (-0.83443195446915219778 - 6.9260695047004095946e-510j)  +/-  (2.56e-118, 2.56e-118j)
| (2.5008279444301536393e-521 + 9.6603656913068182973e-522j)  +/-  (8.31e-520, 8.31e-520j)
| (0.70703197208114496909 + 6.5218712459472367304e-515j)  +/-  (1.76e-119, 1.76e-119j)
| (0.6325404225369935573 - 3.6177180994026584039e-516j)  +/-  (2.77e-120, 2.77e-120j)
| (-0.095404851378700209159 + 6.7793720623068219211e-523j)  +/-  (9.13e-127, 9.13e-127j)
| (-0.77459666924148337704 - 7.9535627115575739535e-516j)  +/-  (7.85e-119, 7.85e-119j)
| (-0.37697617180685685466 + 6.418063815024514992e-521j)  +/-  (4.02e-123, 4.02e-123j)
| (0.37697617180685685466 + 3.2248836091012561549e-521j)  +/-  (3.56e-123, 3.56e-123j)
| (0.77459666924148337704 - 7.9512868148985848909e-518j)  +/-  (7.4e-119, 7.4e-119j)
| (0.095404851378700209159 + 1.1071390687401905248e-525j)  +/-  (9.13e-127, 9.13e-127j)
| (-0.46647921730837471396 - 8.1875708981657863937e-520j)  +/-  (3.61e-122, 3.61e-122j)
| (-0.55202440766185927029 + 2.1270205647035323142e-518j)  +/-  (3.6e-121, 3.6e-121j)
| (0.19047286522906600477 + 1.3713907700645642841e-524j)  +/-  (1.4e-125, 1.4e-125j)
| (0.55202440766185927029 + 6.4237608505288963427e-520j)  +/-  (3.66e-121, 3.66e-121j)
| (0.46647921730837471396 - 4.9212752468103847442e-521j)  +/-  (3.66e-122, 3.66e-122j)
| (-0.28462177099265720081 - 7.7984599256100677571e-524j)  +/-  (2.25e-124, 2.25e-124j)
| (-0.6325404225369935573 - 1.5187585401794486201e-521j)  +/-  (3.09e-120, 3.09e-120j)
| (-0.19047286522906600477 + 1.8805716980806539114e-531j)  +/-  (1.36e-125, 1.36e-125j)
-------------------------------------------------
The weights are:
| (0.017968021411418525805 - 1.3672171180994485234e-451j)  +/-  (1.79e-25, 3.81e-81j)
| (0.027993696562949660857 + 3.6717457800337265978e-451j)  +/-  (1.1e-25, 2.34e-81j)
| (0.037704112837272227564 - 2.4292726330956523291e-451j)  +/-  (6.44e-26, 1.37e-81j)
| (0.0077552051555116041628 + 6.1285699880187546332e-454j)  +/-  (1.32e-27, 2.8e-83j)
| (0.046985883351477510465 + 1.0485683529834552715e-452j)  +/-  (9.38e-28, 2e-83j)
| (0.037704112837272227564 - 7.0988354779274805188e-453j)  +/-  (8.96e-28, 1.91e-83j)
| (0.017968021411418525805 - 2.1686186625102974427e-453j)  +/-  (5.51e-28, 1.17e-83j)
| (0.046985883351477510465 + 1.9953325366242907805e-451j)  +/-  (1.18e-28, 2.5e-84j)
| (0.0077552051555116041628 - 9.4336337758369682497e-452j)  +/-  (2.15e-28, 4.57e-84j)
| (0.027993696562949660857 + 4.3418701551487791339e-453j)  +/-  (2.62e-28, 5.58e-84j)
| (0.055728777453000264957 - 1.4601529750053890728e-452j)  +/-  (1.53e-29, 3.27e-85j)
| (0.093417579659263787473 + 8.1821038482410233227e-452j)  +/-  (6.18e-32, 1.32e-87j)
| (0.071170350329377660293 - 1.5667873680837436408e-451j)  +/-  (3.94e-31, 8.4e-87j)
| (0.055728777453000264957 - 1.7740809218468243039e-451j)  +/-  (4.14e-30, 8.81e-86j)
| (0.095450740848725708985 - 1.2974552158063815246e-451j)  +/-  (2.13e-32, 4.53e-88j)
| (0.071170350329377660293 - 2.5670080726272936756e-452j)  +/-  (1.21e-31, 2.58e-87j)
| (0.077662249777420747993 + 3.3085070532796736153e-452j)  +/-  (4.42e-32, 9.42e-88j)
| (0.095307523586183868765 + 1.4010064176296967287e-451j)  +/-  (3.04e-33, 6.48e-89j)
| (0.063825228744862435985 + 1.6449151501774963204e-451j)  +/-  (2.89e-32, 6.16e-88j)
| (0.091112741935385519717 - 1.4893864632997324326e-451j)  +/-  (3.65e-34, 7.78e-90j)
| (0.091112741935385519717 - 6.6436194335063401726e-452j)  +/-  (8.43e-34, 1.8e-89j)
| (0.063825228744862435985 + 1.9595439065350322553e-452j)  +/-  (1.08e-32, 2.3e-88j)
| (0.095307523586183868765 + 1.1533706083310496858e-451j)  +/-  (4.92e-34, 1.05e-89j)
| (0.087707551344503254363 + 1.4905600547399663375e-451j)  +/-  (4.68e-35, 9.96e-91j)
| (0.083203649842928553175 - 1.4985191225106949393e-451j)  +/-  (3.66e-35, 7.8e-91j)
| (0.094732057584081523932 - 9.8643772267206970618e-452j)  +/-  (9.19e-35, 1.96e-90j)
| (0.083203649842928553175 - 4.2150253040057076696e-452j)  +/-  (2.4e-35, 5.1e-91j)
| (0.087707551344503254363 + 5.3189160198525588095e-452j)  +/-  (1.88e-35, 4.01e-91j)
| (0.093417579659263787473 + 1.4840735410642731108e-451j)  +/-  (1.73e-36, 3.7e-92j)
| (0.077662249777420747993 + 1.5213897033949301743e-451j)  +/-  (9.21e-37, 2.05e-92j)
| (0.094732057584081523932 - 1.4599299187070155456e-451j)  +/-  (1.85e-36, 3.9e-92j)
