Starting with polynomial:
P : 1/2*t^2 - 2*t + 1
Extension levels are: 2 4 9
-------------------------------------------------
Trying to find an order 4 Kronrod extension for:
P1 : 1/2*t^2 - 2*t + 1
Solvable: 1
-------------------------------------------------
Trying to find an order 9 Kronrod extension for:
P2 : 1/2*t^6 - 162/13*t^5 + 101*t^4 - 4208/13*t^3 + 5436/13*t^2 - 2928/13*t + 552/13
Solvable: 1
-------------------------------------------------
Ending with final polynomial:
P : 1/2*t^15 - 335476827161063738460038085879987/2317239277355956082043188523626*t^14 + 85403978234682221205603073844621707/5793098193389890205107971309065*t^13 - 895848123227788341674324195494363979/1158619638677978041021594261813*t^12 + 698157082723792152300616016076248696124/28965490966949451025539856545325*t^11 - 13840549741499437395021956207862287347572/28965490966949451025539856545325*t^10 + 180318505670031407326392103326621091114968/28965490966949451025539856545325*t^9 - 1563309030258537017739913535059990680274008/28965490966949451025539856545325*t^8 + 8999985921255999882829175841094174391134656/28965490966949451025539856545325*t^7 - 33897722050855347368126214831956096056815168/28965490966949451025539856545325*t^6 + 81236044592807573674415276888895204199512192/28965490966949451025539856545325*t^5 - 23750958446768270491099198505657376660911232/5793098193389890205107971309065*t^4 + 19965686219241786564670122543474248843914752/5793098193389890205107971309065*t^3 - 8867449593123421639701012205157426298714624/5793098193389890205107971309065*t^2 + 1760607887430882388143028113180363993725952/5793098193389890205107971309065*t - 90450512222331736517370589764626744613888/5793098193389890205107971309065
-------------------------------------------------
Computing nodes and weights
  current precision for roots: 53
  current precision for roots: 106
 current precision for weights: 53
Linear system for weights solvable: 1
  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:
| (147.6693446445644587 - 6.2107695436191935828e-263j)  +/-  (1.23e-123, 1.23e-123j)
| (35.620029388305712776 + 3.2062185533490362218e-259j)  +/-  (7.88e-122, 7.88e-122j)
| (21.167776560403273767 - 1.9267758646144369752e-260j)  +/-  (7.16e-121, 7.16e-121j)
| (27.27383426648038326 + 1.2653926183239822309e-266j)  +/-  (3.67e-121, 3.67e-121j)
| (2.0823987425257494909 - 8.2296067700226265832e-269j)  +/-  (2.89e-123, 2.89e-123j)
| (5.002186646101764202 - 1.3096824850455943108e-278j)  +/-  (8.94e-122, 8.94e-122j)
| (12.486507079040894342 + 1.0841029108019727322e-294j)  +/-  (7.69e-121, 7.69e-121j)
| (16.358718462629853752 - 1.1614611337111482687e-312j)  +/-  (8.87e-121, 8.87e-121j)
| (3.4142135623730950488 - 1.9054426877803812262e-326j)  +/-  (1.86e-122, 1.86e-122j)
| (0.5857864376269049512 + 1.3932485614506953355e-336j)  +/-  (2.19e-124, 2.19e-124j)
| (1.0406748406401594478 + 8.26295131090286399e-336j)  +/-  (4.89e-124, 4.89e-124j)
| (0.075792852254336018998 + 3.6879420686809667886e-344j)  +/-  (3.27e-127, 3.27e-127j)
| (6.9239565457104964806 + 2.339419697426363001e-360j)  +/-  (2.29e-121, 2.29e-121j)
| (0.47193845768537280597 + 4.1935253427549208736e-375j)  +/-  (1.1e-124, 1.1e-124j)
| (9.3755561754023583291 + 1.3151614410994315079e-375j)  +/-  (4.82e-121, 4.82e-121j)
-------------------------------------------------
The weights are:
| (1.0275540669794700263e-33 + 4.6417953134267670621e-284j)  +/-  (3.32e-65, 5.61e-125j)
| (3.4736668369798958998e-15 - 2.187479070699400204e-273j)  +/-  (9.02e-57, 1.52e-116j)
| (3.4445434025203540518e-09 + 3.9718482483274367413e-269j)  +/-  (2.48e-54, 4.2e-114j)
| (9.9650544691897180009e-12 + 3.542848713454841791e-271j)  +/-  (1.61e-55, 2.73e-115j)
| (0.14837177448248789055 - 1.0865424657597071526e-264j)  +/-  (2.86e-45, 4.83e-105j)
| (0.011597011211883225863 - 1.5245084298113050885e-265j)  +/-  (3.89e-49, 6.57e-109j)
| (1.3111354324271020011e-05 + 1.5074402624172544354e-267j)  +/-  (5.54e-53, 9.36e-113j)
| (3.381306374512935551e-07 - 2.379027508215188858e-268j)  +/-  (6.43e-54, 1.09e-113j)
| (0.048141967540503081039 + 4.1818804709247038892e-265j)  +/-  (1.73e-49, 2.93e-109j)
| (-0.27896982709835221815 - 1.6613113417589640235e-263j)  +/-  (8.75e-48, 1.52e-107j)
| (0.32408855066474318078 + 4.413095826314745307e-264j)  +/-  (4.2e-48, 7.18e-108j)
| (0.18572016513279807749 - 9.506148198434406406e-265j)  +/-  (1.53e-48, 2.63e-108j)
| (0.0021219830568007095222 + 4.3491541831303464259e-266j)  +/-  (1.21e-51, 2.04e-111j)
| (0.55868043027672332799 + 1.3935705204240017484e-263j)  +/-  (2.74e-48, 4.94e-108j)
| (0.00023449179293907195274 - 9.0686813960893919856e-267j)  +/-  (1.58e-52, 2.66e-112j)
