Starting with polynomial:
P : 2*t
Extension levels are: 1 2 10 20
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Trying to find an order 2 Kronrod extension for:
P1 : 2*t
Solvable: 1
-------------------------------------------------
Trying to find an order 10 Kronrod extension for:
P2 : 2*t^3 - 3*t
Solvable: 1
-------------------------------------------------
Trying to find an order 20 Kronrod extension for:
P3 : 2*t^13 - 629/8*t^11 + 17435/16*t^9 - 105435/16*t^7 + 557865/32*t^5 - 2248785/128*t^3 + 1133055/256*t
Solvable: 1
-------------------------------------------------
Ending with final polynomial:
P : 2*t^33 - 3868363632647762340929349819043/10049566913423152616959022136*t^31 + 8430026763398522960166747363195775/261288739749001968040934575536*t^29 - 5693552740397442351951872612613544795/3658042356486027552573084057504*t^27 + 117392946727225262907783260017500713685/2438694904324018368382056038336*t^25 - 4909232891777820073049782510579590086655/4877389808648036736764112076672*t^23 + 142672155640543737221615785127867356682415/9754779617296073473528224153344*t^21 - 416814309165456309181813912986235084703475/2787079890656020992436635472384*t^19 + 6008630303490478509874493928882027275380575/5574159781312041984873270944768*t^17 - 60603219722255771330292820339073608766069175/11148319562624083969746541889536*t^15 + 32346812700406633522862432330061087692360475/1715126086557551379961006444544*t^13 - 150132604097588143758417392423343076769461425/3430252173115102759922012889088*t^11 + 40584555899455401993657516550893544133046375/623682213293655047258547798016*t^9 - 72460347750105257840049530972187649118992125/1247364426587310094517095596032*t^7 + 70489255901535674454493913527506678610924125/2494728853174620189034191192064*t^5 - 32179665974723661869792522467500363649815375/4989457706349240378068382384128*t^3 + 5000311452788290134073272393910186207099875/9978915412698480756136764768256*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
-------------------------------------------------
The nodes are:
| (-3.6646204430745300527 + 9.1524987179991243234e-446j)  +/-  (3.24e-120, 3.24e-120j)
| (-4.1180864274630133413 - 1.5969533740237322662e-446j)  +/-  (3.28e-120, 3.28e-120j)
| (-5.7641747164274131876 + 2.3098939554972498784e-449j)  +/-  (3.74e-121, 3.74e-121j)
| (-4.6140553111741102971 - 1.4640340607792829423e-447j)  +/-  (2.36e-120, 2.36e-120j)
| (2.8945392101898497953 - 1.5288301233284903764e-446j)  +/-  (1.74e-120, 1.74e-120j)
| (4.6140553111741102971 - 2.2165923140614660894e-457j)  +/-  (2.4e-120, 2.4e-120j)
| (5.7641747164274131876 - 2.4949718367767931275e-466j)  +/-  (3.51e-121, 3.51e-121j)
| (-1.5853053020908627356 + 1.4713904310105053233e-471j)  +/-  (2.36e-122, 2.36e-122j)
| (-5.1563737135148691342 - 2.2915965500276218303e-469j)  +/-  (1.34e-120, 1.34e-120j)
| (-3.2595330824338197843 - 2.0748884709927383892e-469j)  +/-  (3.06e-120, 3.06e-120j)
| (3.6646204430745300527 + 9.2249108240013314553e-470j)  +/-  (3.66e-120, 3.66e-120j)
| (1.2247448713915890491 + 2.6512197944212888724e-481j)  +/-  (2.35e-123, 2.35e-123j)
| (-6.4954076508617139041 + 2.847273938714499015e-481j)  +/-  (4.68e-122, 4.68e-122j)
| (-1.2247448713915890491 - 2.9770523927229018079e-481j)  +/-  (2.36e-123, 2.36e-123j)
| (4.1180864274630133413 - 7.6355745065025903157e-480j)  +/-  (3.27e-120, 3.27e-120j)
| (1.5853053020908627356 + 4.2241792237327786654e-485j)  +/-  (2.27e-122, 2.27e-122j)
| (6.4954076508617139041 + 1.3749143353297888382e-486j)  +/-  (5.21e-122, 5.21e-122j)
| (-2.8945392101898497953 + 4.9289584687494964765e-483j)  +/-  (2.07e-120, 2.07e-120j)
| (-0.3910332057349781268 - 5.5289301877149352403e-490j)  +/-  (7.55e-126, 7.55e-126j)
| (-2.5296025834934300893 + 2.1854518904778922642e-484j)  +/-  (8.65e-121, 8.65e-121j)
| (1.8602834494799461889 + 6.4764581510089061263e-485j)  +/-  (1.1e-121, 1.1e-121j)
| (0.83980521104447649256 + 2.9242214495316119054e-491j)  +/-  (2.57e-124, 2.57e-124j)
| (-2.1630525017796250878 - 1.9396180739735863531e-488j)  +/-  (2.87e-121, 2.87e-121j)
| (3.2595330824338197843 + 3.194832556309811739e-488j)  +/-  (3.12e-120, 3.12e-120j)
| (-0.60808265691331281929 + 2.33083330389731764e-498j)  +/-  (6.05e-125, 6.05e-125j)
| (-1.8602834494799461889 + 7.4889084630580255225e-495j)  +/-  (1.04e-121, 1.04e-121j)
| (0.60808265691331281929 - 3.0223602070289160986e-497j)  +/-  (5.28e-125, 5.28e-125j)
| (2.5296025834934300893 - 9.3866224551659634503e-495j)  +/-  (7.94e-121, 7.94e-121j)
| (5.1563737135148691342 - 2.3987003798272255735e-503j)  +/-  (1.15e-120, 1.15e-120j)
| (-0.83980521104447649256 + 3.8855763958356799378e-507j)  +/-  (2.73e-124, 2.73e-124j)
| (-5.0491794656522226786e-510 + 1.5883770223124394743e-510j)  +/-  (1.75e-508, 1.75e-508j)
| (2.1630525017796250878 - 2.7934865734277906668e-508j)  +/-  (3.15e-121, 3.15e-121j)
| (0.3910332057349781268 + 9.9255267787950305606e-516j)  +/-  (6.77e-126, 6.77e-126j)
-------------------------------------------------
The weights are:
| (3.5736203533697133397e-07 + 1.9960535820141958139e-451j)  +/-  (1.99e-32, 2.56e-91j)
| (1.1565547781149712628e-08 + 3.8715221748260978466e-453j)  +/-  (3.26e-34, 4.2e-93j)
| (1.3707281068125487991e-15 - 3.2684007956842576071e-458j)  +/-  (6.22e-40, 8.03e-99j)
| (1.6572302740173285848e-10 - 1.3648700809254948799e-454j)  +/-  (3.07e-36, 3.96e-95j)
| (4.649761900231882578e-05 + 3.6035546285047890268e-450j)  +/-  (1.28e-33, 1.65e-92j)
| (1.6572302740173285848e-10 - 9.8356923280720032501e-456j)  +/-  (6.62e-40, 8.54e-99j)
| (1.3707281068125487991e-15 - 9.9772685653303120056e-460j)  +/-  (4.87e-43, 6.28e-102j)
| (0.014721994268910193954 + 1.7645835183257746856e-448j)  +/-  (1.03e-27, 1.33e-86j)
| (9.1261616919179749675e-13 + 2.6687946905478598609e-456j)  +/-  (2.41e-39, 3.11e-98j)
| (5.213319043301180724e-06 - 8.1708091934152523898e-451j)  +/-  (1.36e-34, 1.76e-93j)
| (3.5736203533697133397e-07 - 1.0884792216316463765e-452j)  +/-  (3.55e-38, 4.58e-97j)
| (0.048313760304841967277 - 2.4082032146917965951e-448j)  +/-  (1.43e-28, 1.85e-87j)
| (2.258952335436588882e-19 + 1.3499290394595347284e-460j)  +/-  (7.35e-44, 9.48e-103j)
| (0.048313760304841967277 - 2.8804280221476766235e-448j)  +/-  (9.61e-29, 1.24e-87j)
| (1.1565547781149712628e-08 + 3.7825472922021946288e-454j)  +/-  (1.76e-39, 2.28e-98j)
| (0.014721994268910193954 + 1.4434590474852920924e-448j)  +/-  (4.02e-32, 5.18e-91j)
| (2.258952335436588882e-19 - 1.275978008486056287e-462j)  +/-  (5.23e-46, 6.75e-105j)
| (4.649761900231882578e-05 + 2.7475152974157521607e-450j)  +/-  (1.61e-35, 2.07e-94j)
| (0.17829413386947098476 + 1.2298907007786817878e-447j)  +/-  (2.48e-31, 3.2e-90j)
| (0.0003487362361618940415 - 9.6161063060311302306e-450j)  +/-  (3.42e-35, 4.41e-94j)
| (0.0045481617363706090372 - 8.5950276068328270196e-449j)  +/-  (5e-35, 6.45e-94j)
| (0.10340927155443487085 + 7.180845430197308176e-448j)  +/-  (1.22e-32, 1.57e-91j)
| (0.0018317554889132691844 + 3.684864421164720933e-449j)  +/-  (1e-34, 1.29e-93j)
| (5.213319043301180724e-06 + 2.6698955975894516498e-451j)  +/-  (9.66e-39, 1.25e-97j)
| (0.036089113730312813099 - 1.4768105048978204563e-447j)  +/-  (1.59e-33, 2.05e-92j)
| (0.0045481617363706090372 - 1.0398602614857616362e-448j)  +/-  (2.37e-34, 3.06e-93j)
| (0.036089113730312813099 - 1.3377718917463629389e-447j)  +/-  (7.53e-34, 9.7e-93j)
| (0.0003487362361618940415 - 1.1408309208847777186e-449j)  +/-  (1.16e-37, 1.49e-96j)
| (9.1261616919179749675e-13 + 1.5837517109376014916e-457j)  +/-  (4.5e-44, 5.82e-103j)
| (0.10340927155443487085 + 8.2012075873065926443e-448j)  +/-  (1.07e-34, 1.4e-93j)
| (0.2247819855566352903 - 7.6282933303267894485e-448j)  +/-  (5.08e-35, 6.62e-94j)
| (0.0018317554889132691844 + 3.2571190009561991109e-449j)  +/-  (4.28e-37, 5.51e-96j)
| (0.17829413386947098476 + 1.1529216723810567215e-447j)  +/-  (4.2e-35, 5.25e-94j)
