Starting with polynomial:
P : 1024*t^10 - 23040*t^8 + 161280*t^6 - 403200*t^4 + 302400*t^2 - 30240
Extension levels are: 10 21
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Trying to find an order 21 Kronrod extension for:
P1 : 1024*t^10 - 23040*t^8 + 161280*t^6 - 403200*t^4 + 302400*t^2 - 30240
Solvable: 1
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Ending with final polynomial:
P : 1024*t^31 - 9781470720/55417*t^29 + 725034827520/55417*t^27 - 2774160628479360/5042947*t^25 + 73543973335128000/5042947*t^23 - 2032532345856610080/7924631*t^21 + 24321748604342936400/7924631*t^19 - 200079533048623320600/7924631*t^17 + 1131280660582006238100/7924631*t^15 - 4355476337984380764750/7924631*t^13 + 861410447564587098975/609587*t^11 - 260064800171087659875/110834*t^9 + 527154492894880323375/221668*t^7 - 590725613789628526125/443336*t^5 + 302310908444829335625/886672*t^3 - 44538274723888425375/1773344*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
Positive weights:   31 out of 31
Indefinite weights: 0 out of 31
Negative weights:   0 out of 31
Extension rule has valid weights: 1
-------------------------------------------------
The nodes are:
| (3.921980288561410489 + 4.879374923577685983e-476j)  +/-  (8.32e-121, 8.32e-121j)
| (-2.973618944580138232 - 4.3369017556528670254e-483j)  +/-  (3.79e-121, 3.79e-121j)
| (-4.9915318402605097928 + 2.019251642370136934e-483j)  +/-  (4.88e-121, 4.88e-121j)
| (3.4361591188377376033 + 6.0825338829414755838e-485j)  +/-  (6.75e-121, 6.75e-121j)
| (5.6088092791497269332 + 1.1881780821475152478e-494j)  +/-  (1.56e-121, 1.56e-121j)
| (-6.3483901213256026444 - 3.014318975009504102e-499j)  +/-  (2.32e-122, 2.32e-122j)
| (6.3483901213256026444 + 1.0135481456592723953e-500j)  +/-  (2.52e-122, 2.52e-122j)
| (-1.3504261902655381033 - 1.6889911038703949798e-502j)  +/-  (1.23e-122, 1.23e-122j)
| (4.4367502754148237658 + 3.6952090103419111646e-500j)  +/-  (7.74e-121, 7.74e-121j)
| (-5.6088092791497269332 + 7.6597459949081732314e-506j)  +/-  (1.77e-121, 1.77e-121j)
| (2.973618944580138232 - 3.3986212472419255188e-505j)  +/-  (3.99e-121, 3.99e-121j)
| (-3.921980288561410489 + 1.8669757946548293098e-507j)  +/-  (7.91e-121, 7.91e-121j)
| (-3.4361591188377376033 - 1.7698949340055481082e-509j)  +/-  (7.06e-121, 7.06e-121j)
| (-1.7566836492998817735 + 4.1798465171880524866e-510j)  +/-  (9.11e-122, 9.11e-122j)
| (4.9915318402605097928 + 1.8572616045121369307e-510j)  +/-  (4.64e-121, 4.64e-121j)
| (1.3504261902655381033 - 1.4678375133543091274e-510j)  +/-  (1.23e-122, 1.23e-122j)
| (-4.4367502754148237658 + 4.0034294868284602497e-511j)  +/-  (7.07e-121, 7.07e-121j)
| (-2.5327316742327897964 - 4.968300002116711329e-510j)  +/-  (2.32e-121, 2.32e-121j)
| (-1.0366108297895136542 - 5.9358699106505727596e-513j)  +/-  (8.68e-124, 8.68e-124j)
| (-0.34290132722370460879 - 1.7675343929869830078e-515j)  +/-  (2.73e-126, 2.73e-126j)
| (1.5791783978242893662 - 1.9460000898270856741e-509j)  +/-  (5.63e-122, 5.63e-122j)
| (0.6938062623744284051 - 2.1795286696403571019e-518j)  +/-  (5.81e-125, 5.81e-125j)
| (1.7566836492998817735 - 2.8497341331564811478e-514j)  +/-  (1.08e-121, 1.08e-121j)
| (2.5327316742327897964 + 1.1290985044071989026e-518j)  +/-  (2.41e-121, 2.41e-121j)
| (-2.1179476066715106381 - 3.9109740032965524715e-526j)  +/-  (1.29e-121, 1.29e-121j)
| (0.34290132722370460879 + 4.0959726493966920057e-528j)  +/-  (2.91e-126, 2.91e-126j)
| (1.0366108297895136542 + 2.1024317787476514108e-526j)  +/-  (8.86e-124, 8.86e-124j)
| (2.1179476066715106381 + 2.3482884962668568104e-532j)  +/-  (1.28e-121, 1.28e-121j)
| (-2.4866634924276492144e-537 + 4.5288100627336888026e-537j)  +/-  (1.6e-535, 1.6e-535j)
| (-0.6938062623744284051 - 9.7460055252667871723e-537j)  +/-  (5.81e-125, 5.81e-125j)
| (-1.5791783978242893662 + 5.403100317918292479e-544j)  +/-  (6.42e-122, 6.42e-122j)
-------------------------------------------------
The weights are:
| (5.8780673908266008441e-08 - 1.5304386943763230228e-482j)  +/-  (3.09e-39, 1.64e-98j)
| (3.6826950711473326504e-05 - 5.1386969891721610955e-482j)  +/-  (3.17e-36, 1.68e-95j)
| (4.9519053394003707587e-12 - 7.9879322149022302252e-487j)  +/-  (5.54e-43, 2.94e-102j)
| (1.9907335741441219582e-06 + 7.2409317772065452493e-482j)  +/-  (4.2e-38, 2.23e-97j)
| (8.1290809917128702351e-15 - 9.2361978643652255217e-488j)  +/-  (6.92e-45, 3.67e-104j)
| (1.5075620694644059136e-18 - 1.0821770455835947972e-490j)  +/-  (2.7e-47, 1.43e-106j)
| (1.5075620694644059136e-18 + 4.5805835405787254299e-490j)  +/-  (7.91e-47, 4.2e-106j)
| (0.027104366679879095305 + 1.5197085495950255211e-478j)  +/-  (1.85e-31, 9.83e-91j)
| (8.4841424052058853863e-10 - 3.4066989447260098544e-484j)  +/-  (4.26e-42, 2.26e-101j)
| (8.1290809917128702351e-15 + 1.6346875052612216195e-488j)  +/-  (9.32e-46, 4.95e-105j)
| (3.6826950711473326504e-05 - 3.7363233076345745355e-481j)  +/-  (4.1e-39, 2.18e-98j)
| (5.8780673908266008441e-08 - 3.6564675480271391752e-484j)  +/-  (1.51e-42, 8.03e-102j)
| (1.9907335741441219582e-06 + 4.7807909048541545547e-483j)  +/-  (1.9e-41, 1.01e-100j)
| (0.0077100998546675577366 + 5.1657932656284090635e-479j)  +/-  (2.73e-37, 1.45e-96j)
| (4.9519053394003707587e-12 + 6.6570586074857212678e-486j)  +/-  (2.41e-45, 1.28e-104j)
| (0.027104366679879095305 + 3.1158246420255407298e-478j)  +/-  (2.09e-37, 1.11e-96j)
| (8.4841424052058853863e-10 + 2.0980002360061985467e-485j)  +/-  (5.94e-44, 3.15e-103j)
| (0.0003966234959990587011 + 4.9575810935008292737e-481j)  +/-  (5.16e-40, 2.74e-99j)
| (0.063536013846266050929 - 1.558050686384486366e-478j)  +/-  (7.58e-37, 4.02e-96j)
| (0.17429978199070572253 - 2.1062184112329770992e-478j)  +/-  (2.13e-37, 1.13e-96j)
| (0.0059490058752018684094 - 2.9293517952416287939e-478j)  +/-  (1.48e-38, 7.83e-98j)
| (0.1224786781252728551 + 2.5293927723117738067e-478j)  +/-  (1.7e-38, 8.95e-98j)
| (0.0077100998546675577366 + 1.3547681083293774069e-478j)  +/-  (2.09e-39, 1.11e-98j)
| (0.0003966234959990587011 + 2.3033710593615275212e-480j)  +/-  (1.06e-41, 5.62e-101j)
| (0.0025243009339343603983 - 4.7984398738202954734e-480j)  +/-  (1.42e-40, 7.49e-100j)
| (0.17429978199070572253 - 2.5097993326156315943e-478j)  +/-  (9.58e-39, 5.04e-98j)
| (0.063536013846266050929 - 2.6775530838775039701e-478j)  +/-  (3.99e-39, 2.1e-98j)
| (0.0025243009339343603983 - 1.6065198598292181556e-479j)  +/-  (4.01e-41, 2.14e-100j)
| (0.19192450375947925747 + 2.4075210597560925536e-478j)  +/-  (2.87e-39, 1.49e-98j)
| (0.1224786781252728551 + 1.7689995339435323124e-478j)  +/-  (7.84e-40, 3.84e-99j)
| (0.0059490058752018684094 - 1.2475374588082585987e-478j)  +/-  (3.64e-40, 2.02e-99j)
