Starting with polynomial:
P : 4096*t^12 - 11264*t^10 + 11520*t^8 - 5376*t^6 + 1120*t^4 - 84*t^2 + 1
Extension levels are: 12 13
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Trying to find an order 13 Kronrod extension for:
P1 : 4096*t^12 - 11264*t^10 + 11520*t^8 - 5376*t^6 + 1120*t^4 - 84*t^2 + 1
Solvable: 1
-------------------------------------------------
Ending with final polynomial:
P : 4096*t^25 - 24576*t^23 + 64768*t^21 - 98560*t^19 + 95760*t^17 - 62016*t^15 + 27132*t^13 - 7956*t^11 + 12155/8*t^9 - 715/4*t^7 + 3003/256*t^5 - 91/256*t^3 + 13/4096*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:
| (-0.12053668025532305335 - 1.5847716310097699766e-469j)  +/-  (6.21e-127, 6.21e-127j)
| (-0.66312265824079520238 + 2.9698226467236200046e-465j)  +/-  (1.03e-121, 1.03e-121j)
| (-0.8854560256532098959 - 2.1547155688573812757e-462j)  +/-  (3.73e-120, 3.73e-120j)
| (0.93501624268541482344 - 1.8339995924569069933e-461j)  +/-  (5.36e-120, 5.36e-120j)
| (0.8854560256532098959 + 3.9746123670773110934e-473j)  +/-  (3.38e-120, 3.38e-120j)
| (0.9927088740980539928 - 8.0175578305080642478e-488j)  +/-  (1.54e-120, 1.54e-120j)
| (0.74851074817110109863 + 7.5955982664409255485e-499j)  +/-  (4.71e-121, 4.71e-121j)
| (-0.93501624268541482344 - 4.4445155338131852543e-502j)  +/-  (4.21e-120, 4.21e-120j)
| (-0.9927088740980539928 + 2.931804030405853359e-503j)  +/-  (1.53e-120, 1.53e-120j)
| (0.97094181742605202716 - 2.236122917433497788e-506j)  +/-  (4.37e-120, 4.37e-120j)
| (0.82298386589365639458 + 1.6403781633056327874e-516j)  +/-  (1.56e-120, 1.56e-120j)
| (0.23931566428755776715 + 8.1538096762512304201e-527j)  +/-  (8.38e-126, 8.38e-126j)
| (-0.97094181742605202716 - 5.1058416602059479432e-522j)  +/-  (4.46e-120, 4.46e-120j)
| (-0.74851074817110109863 - 8.3501363623520453627e-523j)  +/-  (4.4e-121, 4.4e-121j)
| (0.12053668025532305335 + 6.7601063171459538179e-530j)  +/-  (5.19e-127, 5.19e-127j)
| (0.66312265824079520238 + 1.4674010470399130907e-525j)  +/-  (1.03e-121, 1.03e-121j)
| (0.46472317204376854566 + 1.7258390496522450778e-527j)  +/-  (1.53e-123, 1.53e-123j)
| (-0.23931566428755776715 - 7.8239930755637183287e-530j)  +/-  (8.48e-126, 8.48e-126j)
| (-0.82298386589365639458 + 1.1936431821824650002e-526j)  +/-  (1.36e-120, 1.36e-120j)
| (-0.35460488704253562597 + 4.463813331353497597e-532j)  +/-  (1.31e-124, 1.31e-124j)
| (0.35460488704253562597 + 1.3221733603562489981e-530j)  +/-  (1.48e-124, 1.48e-124j)
| (0.56806474673115580251 + 1.6060607775806969408e-530j)  +/-  (1.59e-122, 1.59e-122j)
| (1.4616223059074544728e-536 - 8.410411324688175076e-536j)  +/-  (2.13e-534, 2.13e-534j)
| (-0.46472317204376854566 - 2.3761237326301465303e-530j)  +/-  (1.82e-123, 1.82e-123j)
| (-0.56806474673115580251 - 2.1518641716692305875e-530j)  +/-  (1.75e-122, 1.75e-122j)
-------------------------------------------------
The weights are:
| (0.037902727258193308215 - 7.6552776725140575048e-463j)  +/-  (1.37e-37, 9.9e-96j)
| (0.021548782312602366411 + 4.562414025491940805e-463j)  +/-  (8.49e-38, 6.15e-96j)
| (0.0083064471782470037978 - 1.9364223429757444122e-463j)  +/-  (2.71e-38, 1.97e-96j)
| (0.0048363317659403634878 + 9.9505217180410074367e-463j)  +/-  (1.17e-38, 8.44e-97j)
| (0.0083064471782470037978 - 3.0839632081359178078e-462j)  +/-  (7.94e-39, 5.75e-97j)
| (0.0005588112033451533239 - 1.769992241089802565e-463j)  +/-  (1.12e-39, 8.14e-98j)
| (0.016912756148936095128 - 1.6854523650294665742e-462j)  +/-  (9.29e-40, 6.74e-98j)
| (0.0048363317659403634878 - 1.6288923356665771539e-463j)  +/-  (6.77e-41, 4.91e-99j)
| (0.0005588112033451533239 - 5.9151635461371089035e-465j)  +/-  (7.66e-42, 5.55e-100j)
| (0.0022027687374382712327 + 1.1219520775211965243e-462j)  +/-  (1.58e-39, 1.15e-97j)
| (0.012411444479951237962 + 2.0474645815486446902e-462j)  +/-  (1.23e-39, 8.89e-98j)
| (0.036258769724100190306 + 1.0254303749850555645e-462j)  +/-  (6.4e-42, 4.64e-100j)
| (0.0022027687374382712327 + 3.4347185417134940666e-464j)  +/-  (7.46e-42, 5.41e-100j)
| (0.016912756148936095128 - 4.497634425267488106e-463j)  +/-  (2.58e-42, 1.87e-100j)
| (0.037902727258193308215 - 9.3479919935801819965e-463j)  +/-  (4.3e-42, 3.12e-100j)
| (0.021548782312602366411 + 1.4835582388074408096e-462j)  +/-  (6.25e-42, 4.53e-100j)
| (0.030155091283291457741 + 1.2241597544047855464e-462j)  +/-  (1.77e-42, 1.28e-100j)
| (0.036258769724100190306 + 6.8743515168220419567e-463j)  +/-  (2.24e-43, 1.62e-101j)
| (0.012411444479951237962 + 5.5733022459182645736e-463j)  +/-  (3e-43, 2.17e-101j)
| (0.033625206695598098051 - 6.1499951374624429905e-463j)  +/-  (7.39e-44, 5.36e-102j)
| (0.033625206695598098051 - 1.1210233341671232907e-462j)  +/-  (2.81e-43, 2.04e-101j)
| (0.026050093981587223576 - 1.3406464664293539023e-462j)  +/-  (3.04e-43, 2.2e-101j)
| (0.038461538461538461538 + 8.4817542144379358224e-463j)  +/-  (8.96e-44, 6.49e-102j)
| (0.030155091283291457741 + 5.4999096945245346927e-463j)  +/-  (5.74e-45, 4.2e-103j)
| (0.026050093981587223576 - 4.9551640204420244761e-463j)  +/-  (4.36e-45, 3.11e-103j)
