Starting with polynomial:
P : 5/2*t^3 - 3/2*t
Extension levels are: 3 4 8
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Trying to find an order 4 Kronrod extension for:
P1 : 5/2*t^3 - 3/2*t
Solvable: 1
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Trying to find an order 8 Kronrod extension for:
P2 : 5/2*t^7 - 77/18*t^5 + 3745/1782*t^3 - 155/594*t
Solvable: 1
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Ending with final polynomial:
P : 5/2*t^15 - 646576627207/65912582718*t^13 + 1719421754504545/110930876714394*t^11 - 36142899049575851/2874118169418390*t^9 + 1577324700316391/285731046082530*t^7 - 3801532399394821/3016049930871150*t^5 + 2102662882898711/16286669626704210*t^3 - 233879228435939/59717788631248770*t
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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
Sufficient bits for target precision reached
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The nodes are:
| (0.99383196321275502221 - 4.8508252405587298057e-207j)  +/-  (3.27e-59, 3.27e-59j)
| (-0.99383196321275502221 + 4.9598485718558719883e-212j)  +/-  (3.23e-59, 3.23e-59j)
| (-0.88845923287225699889 + 8.967661056315836217e-214j)  +/-  (2.9e-59, 2.9e-59j)
| (0.62110294673722640294 + 4.3983918569870545691e-214j)  +/-  (1.18e-60, 1.18e-60j)
| (0.88845923287225699889 + 3.1938692166117282122e-218j)  +/-  (3.39e-59, 3.39e-59j)
| (0.96049126870802028342 + 2.832817228868819229e-228j)  +/-  (4.63e-59, 4.63e-59j)
| (-0.96049126870802028342 + 2.0313521324743146783e-230j)  +/-  (4.98e-59, 4.98e-59j)
| (-0.77459666924148337704 + 3.1658239814101434505e-234j)  +/-  (8.44e-60, 8.44e-60j)
| (-0.434243749346802558 - 1.9344889141802522812e-236j)  +/-  (1.22e-61, 1.22e-61j)
| (0.434243749346802558 + 4.9633485849709355479e-235j)  +/-  (1.11e-61, 1.11e-61j)
| (0.77459666924148337704 + 3.4387579287372475409e-240j)  +/-  (8.77e-60, 8.77e-60j)
| (0.22338668642896688163 - 3.9027907044967629905e-243j)  +/-  (7.94e-63, 7.94e-63j)
| (-0.22338668642896688163 - 1.9560864815032735293e-242j)  +/-  (9.09e-63, 9.09e-63j)
| (-0.62110294673722640294 - 3.7817366861632075744e-242j)  +/-  (1.2e-60, 1.2e-60j)
| (-2.0437226516031033132e-269 - 7.5026766571943700909e-271j)  +/-  (3.07e-268, 3.07e-268j)
-------------------------------------------------
The weights are:
| (0.017001719629940260339 + 4.5418731566516074399e-207j)  +/-  (1.14e-17, 4.18e-45j)
| (0.017001719629940260339 + 4.1538284013543298413e-209j)  +/-  (4.2e-18, 1.54e-45j)
| (0.092927195315124537686 + 1.3819130859539552851e-208j)  +/-  (3.37e-18, 1.24e-45j)
| (0.17151190913639138079 + 6.9204787953183991758e-208j)  +/-  (1.23e-18, 4.51e-46j)
| (0.092927195315124537686 + 2.4680891388135045224e-207j)  +/-  (8e-19, 2.93e-46j)
| (0.051603282997079739697 - 6.2203591351774025037e-207j)  +/-  (9.73e-19, 3.57e-46j)
| (0.051603282997079739697 - 1.0618175493620682515e-208j)  +/-  (5.76e-19, 2.12e-46j)
| (0.13441525524378422036 - 1.5114731956259552783e-208j)  +/-  (1.41e-19, 5.19e-47j)
| (0.20062852937698902103 - 1.7245911169797468876e-208j)  +/-  (2.32e-20, 8.47e-48j)
| (0.20062852937698902103 - 4.4010736857152726674e-208j)  +/-  (1.59e-20, 5.81e-48j)
| (0.13441525524378422036 - 1.2191031378026337512e-207j)  +/-  (3.84e-20, 1.4e-47j)
| (0.2191568584015874964 + 3.088908382400205756e-208j)  +/-  (3.17e-21, 1.15e-48j)
| (0.2191568584015874964 + 1.9551615714037870241e-208j)  +/-  (1.27e-21, 4.84e-49j)
| (0.17151190913639138079 + 1.5973244468140179943e-208j)  +/-  (1.54e-21, 6.24e-49j)
| (0.22551049979820668739 - 2.3652137991935122078e-208j)  +/-  (9.62e-22, 3.37e-49j)
