Starting with polynomial:
P : t^8 - 28*t^6 + 210*t^4 - 420*t^2 + 105
Extension levels are: 8 17
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Trying to find an order 17 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^25 - 452828/1227*t^23 + 685960534/13497*t^21 - 80933563396/22495*t^19 + 9962249121419/67485*t^17 - 49910032290664/13497*t^15 + 258867717314332/4499*t^13 - 2485498938927368/4499*t^11 + 1300482287966407/409*t^9 - 4240049096592036/409*t^7 + 7081688823471990/409*t^5 - 5006672358318540/409*t^3 + 952148658919185/409*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:
| (4.8893735663562835099 + 1.2253383690323824972e-341j)  +/-  (5.09e-122, 5.09e-122j)
| (-12.824251389140315062 - 4.9172560915746223848e-344j)  +/-  (2.52e-124, 2.52e-124j)
| (-7.6694308111061612277 + 2.2988335700720786997e-347j)  +/-  (7.77e-123, 7.77e-123j)
| (7.6694308111061612277 - 3.3908169317672873073e-352j)  +/-  (7.38e-123, 7.38e-123j)
| (12.824251389140315062 + 8.2188627803525870635e-355j)  +/-  (2.58e-124, 2.58e-124j)
| (6.5948328212643071392 - 9.3539777428063098131e-353j)  +/-  (3.03e-122, 3.03e-122j)
| (5.6962016737669063338 + 3.6539253783624281502e-362j)  +/-  (5.42e-122, 5.42e-122j)
| (-4.8893735663562835099 + 2.2655192226490393975e-373j)  +/-  (4.79e-122, 4.79e-122j)
| (-4.1445471861258943321 + 4.159066028876591262e-388j)  +/-  (3.36e-122, 3.36e-122j)
| (2.2018315284563954933 - 3.8668184890072328556e-399j)  +/-  (1.57e-123, 1.57e-123j)
| (1.6365190424351079992 - 5.5547180941010366111e-399j)  +/-  (2.87e-124, 2.87e-124j)
| (4.1445471861258943321 - 2.3327635909627965206e-396j)  +/-  (3.35e-122, 3.35e-122j)
| (-3.4498309071406050982 + 1.1175438779652369093e-400j)  +/-  (1.62e-122, 1.62e-122j)
| (-2.2018315284563954933 - 1.1444541142254893763e-407j)  +/-  (1.38e-123, 1.38e-123j)
| (-2.5299044004070088408e-419 + 5.2332879596990697164e-419j)  +/-  (1.45e-417, 1.45e-417j)
| (0.53907981135137510807 - 7.6094898253339224544e-416j)  +/-  (3.33e-126, 3.33e-126j)
| (3.4498309071406050982 - 7.6400554652961975425e-413j)  +/-  (1.7e-122, 1.7e-122j)
| (-1.6365190424351079992 - 6.8379701793858010383e-419j)  +/-  (2.94e-124, 2.94e-124j)
| (-1.0851172237661274457 + 4.9288113356754066499e-425j)  +/-  (3.24e-125, 3.24e-125j)
| (-5.6962016737669063338 + 1.4595551624182202036e-428j)  +/-  (5.13e-122, 5.13e-122j)
| (2.8024858612875416991 - 4.76644939501973655e-440j)  +/-  (5.53e-123, 5.53e-123j)
| (1.0851172237661274457 + 2.4044890221454611925e-444j)  +/-  (3.69e-125, 3.69e-125j)
| (-2.8024858612875416991 - 1.8444352989719918249e-441j)  +/-  (5.77e-123, 5.77e-123j)
| (-6.5948328212643071392 + 1.0875934466921637952e-456j)  +/-  (2.91e-122, 2.91e-122j)
| (-0.53907981135137510807 - 7.7278162300740674711e-472j)  +/-  (3.33e-126, 3.33e-126j)
-------------------------------------------------
The weights are:
| (1.9854598127157182759e-06 - 7.3181815488877132172e-347j)  +/-  (6.4e-43, 1.49e-103j)
| (4.1456390913733939898e-26 - 7.9884819772507890039e-359j)  +/-  (2.28e-53, 5.33e-114j)
| (8.3087217862647717381e-14 + 1.1988018067679438342e-352j)  +/-  (3.48e-48, 8.13e-109j)
| (8.3087217862647717381e-14 - 5.415541858731862973e-352j)  +/-  (1.95e-48, 4.56e-109j)
| (4.1456390913733939898e-26 + 1.7833289611874319271e-358j)  +/-  (2.88e-54, 6.73e-115j)
| (1.3824584252583381164e-10 + 5.2893481598198706588e-350j)  +/-  (4.23e-47, 9.89e-108j)
| (3.035776710451939078e-08 - 2.4529568006963190059e-348j)  +/-  (7.17e-46, 1.68e-106j)
| (1.9854598127157182759e-06 - 2.4879057271196520501e-348j)  +/-  (2.56e-47, 5.97e-108j)
| (5.3391934239122767809e-05 + 2.1987924342661311081e-347j)  +/-  (3.68e-46, 8.59e-107j)
| (0.020479785438183308182 - 6.2097883271789276447e-345j)  +/-  (6.32e-42, 1.48e-102j)
| (0.058046487954878996757 + 1.2240260222938838224e-344j)  +/-  (1.82e-40, 4.25e-101j)
| (5.3391934239122767809e-05 + 2.6668921867602222216e-346j)  +/-  (2.34e-45, 5.46e-106j)
| (0.0006971697973765421131 - 1.4040517425510138493e-346j)  +/-  (4.48e-46, 1.04e-106j)
| (0.020479785438183308182 - 2.353488155302209585e-345j)  +/-  (2.62e-44, 6.13e-105j)
| (0.21430582220382900936 - 2.3619058971750502531e-344j)  +/-  (1.32e-41, 3.07e-102j)
| (0.18711841081197660778 + 2.3569951219960840323e-344j)  +/-  (9.45e-42, 2.2e-102j)
| (0.0006971697973765421131 - 8.1336072051072869611e-346j)  +/-  (2.15e-45, 5.03e-106j)
| (0.058046487954878996757 + 6.1012015158699961156e-345j)  +/-  (1.36e-43, 3.21e-104j)
| (0.12154900023022403893 - 1.2062706854960067273e-344j)  +/-  (4.71e-43, 1.1e-103j)
| (3.035776710451939078e-08 + 1.8696334037561895841e-349j)  +/-  (6.47e-50, 1.54e-110j)
| (0.004900826775298128801 + 2.4637025093830390141e-345j)  +/-  (2.61e-45, 5.71e-106j)
| (0.12154900023022403893 - 1.8944183692043635092e-344j)  +/-  (8.18e-44, 1.82e-104j)
| (0.004900826775298128801 + 6.6843011539107812661e-346j)  +/-  (4.17e-46, 8.71e-107j)
| (1.3824584252583381164e-10 - 7.8549336286825101546e-351j)  +/-  (2.14e-51, 5.24e-112j)
| (0.18711841081197660778 + 1.8888660267240951587e-344j)  +/-  (4.34e-44, 6.55e-105j)
