Starting with polynomial:
P : t^2 - 1
Extension levels are: 2 18
-------------------------------------------------
Trying to find an order 18 Kronrod extension for:
P1 : t^2 - 1
Solvable: 1
-------------------------------------------------
Ending with final polynomial:
P : t^20 - 102461303/565904*t^18 + 7451164719/565904*t^16 - 70640397585/141476*t^14 + 1518998116545/141476*t^12 - 37776477764025/282952*t^10 + 265885539384465/282952*t^8 - 496894991077485/141476*t^6 + 866285443848825/141476*t^4 - 2135714078472975/565904*t^2 + 196133364001575/565904
-------------------------------------------------
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:
| (1.6772285862804930392 + 2.4836243798296210424e-409j)  +/-  (9.23e-125, 9.23e-125j)
| (-3.8258221952756218653 + 2.3594431608381399903e-410j)  +/-  (5.28e-123, 5.28e-123j)
| (-6.3716403606486743892 - 1.9299556425962038871e-419j)  +/-  (6.28e-123, 6.28e-123j)
| (-7.4772382135676234718 + 1.3511147157935380467e-425j)  +/-  (1.43e-123, 1.43e-123j)
| (4.6070279582392740597 - 4.0660539318563505471e-427j)  +/-  (9.59e-123, 9.59e-123j)
| (6.3716403606486743892 - 1.1646147851177957693e-428j)  +/-  (6.25e-123, 6.25e-123j)
| (7.4772382135676234718 + 1.3800348609777348711e-429j)  +/-  (1.5e-123, 1.5e-123j)
| (2.3697606219775603169 - 2.6927509482492387729e-430j)  +/-  (5.5e-124, 5.5e-124j)
| (-2.3697606219775603169 + 1.2386654361946498355e-428j)  +/-  (5.07e-124, 5.07e-124j)
| (-4.6070279582392740597 + 6.9095449639636116728e-435j)  +/-  (1.04e-122, 1.04e-122j)
| (3.0835439422030643755 + 4.3837864699218129349e-439j)  +/-  (2.15e-123, 2.15e-123j)
| (5.4444225157700206277 + 6.1226068015667778421e-443j)  +/-  (9.83e-123, 9.83e-123j)
| (-1.6772285862804930392 - 3.3674337408617278131e-441j)  +/-  (8.36e-125, 8.36e-125j)
| (-3.0835439422030643755 - 1.6695813010435109512e-448j)  +/-  (2.11e-123, 2.11e-123j)
| (-5.4444225157700206277 + 4.4567614471963799549e-465j)  +/-  (1.07e-122, 1.07e-122j)
| (3.8258221952756218653 + 6.5686437955629573505e-470j)  +/-  (5.67e-123, 5.67e-123j)
| (1 - 1.1712471473706008511e-471j)  +/-  (1.08e-125, 1.08e-125j)
| (-0.33225196463772179867 + 6.12791677619154569e-472j)  +/-  (9.14e-127, 9.14e-127j)
| (-1 - 1.143324373883028537e-472j)  +/-  (1.08e-125, 1.08e-125j)
| (0.33225196463772179867 + 4.4334072598494827395e-477j)  +/-  (9.14e-127, 9.14e-127j)
-------------------------------------------------
The weights are:
| (0.066844409070315246134 - 1.5727291933353981762e-410j)  +/-  (8.83e-34, 7.73e-96j)
| (0.00020097018754605091191 - 1.1440809156707263162e-412j)  +/-  (6.41e-41, 5.61e-103j)
| (6.0517975552227322182e-10 + 1.0754984730088132525e-415j)  +/-  (2.53e-45, 2.22e-107j)
| (3.6625904871437925247e-13 - 2.0401051813694156953e-417j)  +/-  (9.55e-47, 8.36e-109j)
| (7.9089497246688416235e-06 + 4.1586773418960904001e-413j)  +/-  (1.36e-44, 1.19e-106j)
| (6.0517975552227322182e-10 + 1.8101812258258833556e-415j)  +/-  (2.19e-47, 1.92e-109j)
| (3.6625904871437925247e-13 - 3.1762072684307622852e-417j)  +/-  (7.17e-49, 6.28e-111j)
| (0.0168991677377016696 - 1.1086967130890871343e-410j)  +/-  (1.28e-41, 1.12e-103j)
| (0.0168991677377016696 - 1.8591913310065569073e-411j)  +/-  (1.04e-42, 9.12e-105j)
| (7.9089497246688416235e-06 + 2.0421520773212250885e-413j)  +/-  (7.04e-46, 6.17e-108j)
| (0.0024976929510389292689 + 1.9049562916057113313e-411j)  +/-  (6.92e-44, 6.06e-106j)
| (1.2764522407333719577e-07 - 3.6764792703716557894e-414j)  +/-  (9.3e-47, 8.14e-109j)
| (0.066844409070315246134 + 4.8955006896982972029e-411j)  +/-  (5.21e-43, 4.56e-105j)
| (0.0024976929510389292689 + 5.3690953223122291334e-412j)  +/-  (9.49e-45, 8.31e-107j)
| (1.2764522407333719577e-07 - 1.9985273644554117774e-414j)  +/-  (1.9e-47, 1.67e-109j)
| (0.00020097018754605091191 - 3.1859368999519916583e-412j)  +/-  (9.25e-46, 8.09e-108j)
| (0.16248073894066201371 + 4.0676706102407722322e-410j)  +/-  (1.8e-43, 1.56e-105j)
| (0.25106898391224133363 + 1.7581384957016687521e-410j)  +/-  (6.13e-44, 5.45e-106j)
| (0.16248073894066201371 - 1.0231837501589185364e-410j)  +/-  (3.51e-44, 3.26e-106j)
| (0.25106898391224133363 - 2.6313784533771553874e-410j)  +/-  (4.24e-44, 3.37e-106j)
