Starting with polynomial:
P : t^14 - 91*t^12 + 3003*t^10 - 45045*t^8 + 315315*t^6 - 945945*t^4 + 945945*t^2 - 135135
Extension levels are: 14 21
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Trying to find an order 21 Kronrod extension for:
P1 : t^14 - 91*t^12 + 3003*t^10 - 45045*t^8 + 315315*t^6 - 945945*t^4 + 945945*t^2 - 135135
Solvable: 1
-------------------------------------------------
Ending with final polynomial:
P : t^35 - 4763482648539713/11262409137338*t^33 + 884488674740708499/11262409137338*t^31 - 95399140335561263355/11262409137338*t^29 + 6666387640870705193985/11262409137338*t^27 - 318790013393155641990345/11262409137338*t^25 + 10745324191545249395291895/11262409137338*t^23 - 259152660541990078383916935/11262409137338*t^21 + 4494632869085547087601819425/11262409137338*t^19 - 55885524417005774309174715975/11262409137338*t^17 + 492824432895525786367033670025/11262409137338*t^15 - 3023536076434530384798724679025/11262409137338*t^13 + 12526366530787745400662573751075/11262409137338*t^11 - 33523359691647467115337968979875/11262409137338*t^9 + 54218777654213764582818516814125/11262409137338*t^7 - 47677020587632395731353659202125/11262409137338*t^5 + 18784825074919843024745829794625/11262409137338*t^3 - 1028588791130251771826595939750/5631204568669*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: 0
  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:
| (-5.4582308317583902378 + 3.7747575541057056695e-464j)  +/-  (1.63e-119, 1.63e-119j)
| (7.5341743781616375289 + 2.367519137142496241e-469j)  +/-  (4.37e-120, 4.37e-120j)
| (-8.383717324881726235 + 2.0796096837207992648e-468j)  +/-  (1.13e-120, 1.13e-120j)
| (-7.5341743781616375289 - 1.090199410649037914e-469j)  +/-  (3.76e-120, 3.76e-120j)
| (2.5622148041921096713 + 2.4378126199200267735e-475j)  +/-  (2.06e-121, 2.06e-121j)
| (9.4074100500362421585 - 4.8403559017282152514e-475j)  +/-  (1.43e-121, 1.43e-121j)
| (2.088344745701944171 - 4.202614585652691688e-476j)  +/-  (2.97e-122, 2.97e-122j)
| (6.7776089877079306073 - 9.368091242062497435e-473j)  +/-  (8.81e-120, 8.81e-120j)
| (-2.5622148041921096713 + 6.7503069734102785514e-475j)  +/-  (1.96e-121, 1.96e-121j)
| (4.3900278648462050443 + 1.4461539568620958334e-472j)  +/-  (1e-119, 1e-119j)
| (-6.7776089877079306073 - 1.7329375995498263422e-472j)  +/-  (8.73e-120, 8.73e-120j)
| (-1.242688955485464179 + 4.6380579729329319887e-487j)  +/-  (6.73e-124, 6.73e-124j)
| (6.0874095469012913223 + 1.4233950246511041617e-481j)  +/-  (1.3e-119, 1.3e-119j)
| (-6.0874095469012913223 + 2.6072201763008707371e-481j)  +/-  (1.43e-119, 1.43e-119j)
| (3.8869245750597693838 + 1.2529594707488707172e-490j)  +/-  (4.92e-120, 4.92e-120j)
| (8.383717324881726235 + 3.7730424500852868245e-493j)  +/-  (1.19e-120, 1.19e-120j)
| (-0.41259045795460183817 + 1.7628398142690265642e-497j)  +/-  (3.75e-126, 3.75e-126j)
| (3.3891820243198009588 - 3.6814852409423634561e-492j)  +/-  (1.94e-120, 1.94e-120j)
| (-2.088344745701944171 + 1.7648662095600857763e-496j)  +/-  (2.56e-122, 2.56e-122j)
| (-9.4074100500362421585 + 2.8863714815342167115e-493j)  +/-  (1.43e-121, 1.43e-121j)
| (1.242688955485464179 - 1.3027816980275296225e-495j)  +/-  (7.3e-124, 7.3e-124j)
| (-4.8969363973455646837 - 1.0771616388197542375e-490j)  +/-  (1.43e-119, 1.43e-119j)
| (-3.8869245750597693838 - 5.6672075742708726012e-500j)  +/-  (4.86e-120, 4.86e-120j)
| (-1.6175811170127585627 + 2.3666323181364807324e-512j)  +/-  (3.75e-123, 3.75e-123j)
| (4.8969363973455646837 - 3.0663054096091397349e-509j)  +/-  (1.5e-119, 1.5e-119j)
| (2.9630365798386675025 + 9.2598117154390097363e-514j)  +/-  (7.64e-121, 7.64e-121j)
| (0.857673053213338801 + 6.3454672417551078869e-516j)  +/-  (6.37e-125, 6.37e-125j)
| (-4.3900278648462050443 + 2.1771793652452838786e-512j)  +/-  (9.74e-120, 9.74e-120j)
| (-2.9630365798386675025 - 7.6965262112048721863e-514j)  +/-  (7.77e-121, 7.77e-121j)
| (1.6175811170127585627 + 2.8191737323643733502e-525j)  +/-  (3.64e-123, 3.64e-123j)
| (-3.3891820243198009588 + 1.0108969663733949727e-525j)  +/-  (2.05e-120, 2.05e-120j)
| (0.41259045795460183817 - 6.343884669541835631e-533j)  +/-  (3.75e-126, 3.75e-126j)
| (1.8894604398031860284e-539 + 1.5945216337317023193e-538j)  +/-  (5.62e-537, 5.62e-537j)
| (5.4582308317583902378 - 2.9727460071973613143e-529j)  +/-  (1.64e-119, 1.64e-119j)
| (-0.857673053213338801 + 4.6474121041916469337e-535j)  +/-  (6.37e-125, 6.37e-125j)
-------------------------------------------------
The weights are:
| (8.0770507530746917578e-08 + 1.3544172108260223588e-470j)  +/-  (3.09e-31, 1.4e-89j)
| (1.4990312213590645719e-13 - 1.8219110606634502612e-476j)  +/-  (9.19e-37, 4.17e-95j)
| (1.9924472618629307349e-16 - 1.234949519300838687e-477j)  +/-  (5.28e-38, 2.39e-96j)
| (1.4990312213590645719e-13 + 1.1402407523764946745e-475j)  +/-  (2.29e-36, 1.04e-94j)
| (0.0066018912293446444828 + 7.1296808612939329065e-468j)  +/-  (1.63e-23, 7.39e-82j)
| (2.8539195415094885164e-20 - 1.1727081707583977942e-480j)  +/-  (3.93e-41, 1.78e-99j)
| (0.022083558460254768964 - 1.7092170649264165659e-467j)  +/-  (1.27e-21, 5.76e-80j)
| (3.0479420438537346475e-11 + 6.7691866793278445742e-475j)  +/-  (2e-36, 9.04e-95j)
| (0.0066018912293446444828 + 1.9745472856984595622e-467j)  +/-  (2.92e-26, 1.33e-84j)
| (1.2968659737396588975e-05 + 2.3147790018390199382e-470j)  +/-  (7.78e-32, 3.53e-90j)
| (3.0479420438537346475e-11 - 6.2776882079754358714e-474j)  +/-  (4.84e-37, 2.19e-95j)
| (0.063302869860882087344 - 1.4712758788244616287e-466j)  +/-  (3.82e-20, 1.73e-78j)
| (2.3650649053314876008e-09 - 1.642616950778584754e-473j)  +/-  (9.07e-36, 4.11e-94j)
| (2.3650649053314876008e-09 + 3.0142527329830895946e-472j)  +/-  (5.69e-36, 2.58e-94j)
| (0.00010623115468476130207 - 1.3757378195284434163e-469j)  +/-  (2.65e-31, 1.2e-89j)
| (1.9924472618629307349e-16 + 2.6100556070623685254e-478j)  +/-  (2.79e-40, 1.27e-98j)
| (0.16014430462212895798 - 1.8140435248524810724e-466j)  +/-  (5.29e-24, 2.4e-82j)
| (0.0006054279997814289807 + 7.6371120286810031801e-469j)  +/-  (2.68e-30, 1.21e-88j)
| (0.022083558460254768964 - 3.8276467826432191156e-467j)  +/-  (2.05e-28, 9.27e-87j)
| (2.8539195415094885164e-20 + 4.4143567204932930462e-480j)  +/-  (1.19e-43, 5.39e-102j)
| (0.063302869860882087344 - 9.2557825846763264792e-467j)  +/-  (7.02e-26, 3.18e-84j)
| (1.3053583686557017499e-06 - 5.821608325730675019e-470j)  +/-  (9.45e-36, 4.29e-94j)
| (0.00010623115468476130207 - 8.1820332415994694311e-469j)  +/-  (8.6e-35, 3.9e-93j)
| (0.046538082822621732956 + 8.6948392361896786675e-467j)  +/-  (2.06e-29, 9.37e-88j)
| (1.3053583686557017499e-06 - 3.1555638940903356329e-471j)  +/-  (2.89e-36, 1.32e-94j)
| (0.0019032802140294997022 - 2.9034736971683848947e-468j)  +/-  (2.45e-32, 1.11e-90j)
| (0.1196390004364415525 + 1.2478549296031629864e-466j)  +/-  (1.04e-29, 4.73e-88j)
| (1.2968659737396588975e-05 + 2.1341015933580163879e-469j)  +/-  (1.26e-35, 5.69e-94j)
| (0.0019032802140294997022 - 9.7992059642106165744e-468j)  +/-  (6.53e-34, 2.96e-92j)
| (0.046538082822621732956 + 4.7194352039554373545e-467j)  +/-  (1.74e-32, 7.94e-91j)
| (0.0006054279997814289807 + 3.2656872960504771031e-468j)  +/-  (1.18e-34, 5.35e-93j)
| (0.16014430462212895798 - 1.5590683279704173126e-466j)  +/-  (6.99e-32, 3.03e-90j)
| (0.15812199203104510916 + 1.8468909926716839603e-466j)  +/-  (3.4e-32, 1.49e-90j)
| (8.0770507530746917578e-08 + 2.7929324069854777438e-472j)  +/-  (9.22e-39, 4.91e-97j)
| (0.1196390004364415525 + 1.7131251614783418856e-466j)  +/-  (1.25e-32, 4.76e-91j)
