Starting with polynomial:
P : t^8 - 28*t^6 + 210*t^4 - 420*t^2 + 105
Extension levels are: 8 16
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Trying to find an order 16 Kronrod extension for:
P1 : t^8 - 28*t^6 + 210*t^4 - 420*t^2 + 105
Solvable: 1
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Ending with final polynomial:
P : t^24 - 42379148/205799*t^22 + 17887751826/1028995*t^20 - 808842426868/1028995*t^18 + 4300571720081/205799*t^16 - 69530951380632/205799*t^14 + 684646567527468/205799*t^12 - 364218257071032/18709*t^10 + 1200200825947851/18709*t^8 - 2018245163718420/18709*t^6 + 1439457643268190/18709*t^4 - 291209545596060/18709*t^2 + 4752962138925/18709
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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:
| (-4.8966461874932643568 - 3.0665820439661211727e-474j)  +/-  (3.47e-122, 3.47e-122j)
| (-6.6238970804854727473 + 6.3933187290089164078e-475j)  +/-  (1.62e-122, 1.62e-122j)
| (-4.1445471861258943321 - 1.5476621707110921564e-476j)  +/-  (2.83e-122, 2.83e-122j)
| (-5.7132104700947026531 - 2.1194164075303297486e-480j)  +/-  (3.31e-122, 3.31e-122j)
| (5.7132104700947026531 + 8.5690349330491727058e-480j)  +/-  (3.22e-122, 3.22e-122j)
| (6.6238970804854727473 + 9.1535277961474363544e-488j)  +/-  (1.73e-122, 1.73e-122j)
| (4.8966461874932643568 + 1.283609998773666896e-496j)  +/-  (3.29e-122, 3.29e-122j)
| (-3.4466385127312596091 + 9.4909677162993425645e-506j)  +/-  (1.36e-122, 1.36e-122j)
| (3.4466385127312596091 - 4.3593129874752903957e-511j)  +/-  (1.35e-122, 1.35e-122j)
| (-7.7146049376391150506 - 3.2055992753032142171e-519j)  +/-  (3.7e-123, 3.7e-123j)
| (1.6365190424351079992 - 2.9577436612333780663e-519j)  +/-  (2.44e-124, 2.44e-124j)
| (0.13363729929066999437 - 1.790135558976070832e-523j)  +/-  (3.01e-127, 3.01e-127j)
| (-0.53907981135137510807 - 5.3734322581546509256e-522j)  +/-  (3.55e-126, 3.55e-126j)
| (-1.6365190424351079992 + 1.2108779479036786951e-520j)  +/-  (2.74e-124, 2.74e-124j)
| (1.0700466874034161396 + 1.3764377526143895614e-521j)  +/-  (2.85e-125, 2.85e-125j)
| (-2.8024858612875416991 - 9.2284906972002326816e-519j)  +/-  (5.16e-123, 5.16e-123j)
| (-0.13363729929066999437 - 2.5906539251379053238e-524j)  +/-  (3.01e-127, 3.01e-127j)
| (7.7146049376391150506 + 1.6384934279069767417e-520j)  +/-  (3.74e-123, 3.74e-123j)
| (-2.2076482213266448141 + 1.2199143504999748047e-521j)  +/-  (1.38e-123, 1.38e-123j)
| (2.2076482213266448141 + 5.1560946733888237345e-523j)  +/-  (1.42e-123, 1.42e-123j)
| (4.1445471861258943321 + 2.8619750776039288854e-529j)  +/-  (2.77e-122, 2.77e-122j)
| (0.53907981135137510807 - 6.1178373427424577347e-542j)  +/-  (3.55e-126, 3.55e-126j)
| (2.8024858612875416991 + 4.0781208495964737028e-540j)  +/-  (5.74e-123, 5.74e-123j)
| (-1.0700466874034161396 + 1.1340243901489349646e-544j)  +/-  (3.3e-125, 3.3e-125j)
-------------------------------------------------
The weights are:
| (1.9374817663969774365e-06 - 1.9603191885746057997e-479j)  +/-  (4.54e-43, 1.79e-103j)
| (1.156877691419869765e-10 + 7.9326537621963677225e-483j)  +/-  (1.6e-46, 6.32e-107j)
| (5.3810379202921402683e-05 + 7.950675236651440201e-479j)  +/-  (2.6e-42, 1.02e-102j)
| (2.7902612907106336337e-08 - 4.6316940115543078675e-481j)  +/-  (6.63e-45, 2.61e-105j)
| (2.7902612907106336337e-08 - 3.503189932992176092e-482j)  +/-  (2.96e-48, 1.16e-108j)
| (1.156877691419869765e-10 + 1.1343545122463432953e-483j)  +/-  (7.72e-50, 3.04e-110j)
| (1.9374817663969774365e-06 + 5.9497310098062435312e-481j)  +/-  (2.64e-47, 1.04e-107j)
| (0.00070516698166672389323 - 3.1137191891950512293e-478j)  +/-  (5.95e-44, 2.34e-104j)
| (0.00070516698166672389323 + 5.4735153230445739459e-479j)  +/-  (1.48e-45, 5.81e-106j)
| (5.9642960835155418045e-14 - 5.623653132447271319e-485j)  +/-  (6.89e-51, 2.71e-111j)
| (0.059498414095787973649 - 5.1807240450549971562e-477j)  +/-  (1.14e-41, 4.49e-102j)
| (0.12068444753246710567 + 1.4065549295194918092e-475j)  +/-  (1.88e-39, 7.41e-100j)
| (0.16831290530703614177 + 6.9634966008254045388e-476j)  +/-  (8.43e-40, 3.32e-100j)
| (0.059498414095787973649 + 1.0365799664491511139e-476j)  +/-  (1.43e-41, 5.64e-102j)
| (0.12575476830343217314 + 1.6785327549573429469e-476j)  +/-  (4.04e-40, 1.59e-100j)
| (0.0048516096080187532486 + 1.2107692801796602485e-477j)  +/-  (6.91e-44, 2.72e-104j)
| (0.12068444753246710567 - 1.4853325115562083598e-475j)  +/-  (6.15e-40, 2.42e-100j)
| (5.9642960835155418045e-14 - 1.2640201923554716082e-485j)  +/-  (1.6e-52, 6.31e-113j)
| (0.020136912292261491039 - 3.8810219752914948661e-477j)  +/-  (2.47e-43, 9.72e-104j)
| (0.020136912292261491039 + 1.4728128551579553434e-477j)  +/-  (1.09e-44, 4.29e-105j)
| (5.3810379202921402683e-05 - 6.7042898208591330753e-480j)  +/-  (1.62e-47, 6.42e-108j)
| (0.16831290530703614177 - 5.5846446248932930591e-476j)  +/-  (4.22e-43, 1.81e-103j)
| (0.0048516096080187532486 - 3.3088148478754122241e-478j)  +/-  (7.84e-46, 3.05e-106j)
| (0.12575476830343217314 - 2.6149511674820868988e-476j)  +/-  (4.53e-44, 1.98e-104j)
