Starting with polynomial:
P : -1/6*t^3 + 3/2*t^2 - 3*t + 1
Extension levels are: 3 15
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Trying to find an order 15 Kronrod extension for:
P1 : -1/6*t^3 + 3/2*t^2 - 3*t + 1
Solvable: 1
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Ending with final polynomial:
P : -1/6*t^18 + 7680232233180119033093847/163258920614834456671948*t^17 - 961082676968379370456500069/163258920614834456671948*t^16 + 141149586961944740492705545171/326517841229668913343896*t^15 - 6786837655976248015447863580275/326517841229668913343896*t^14 + 112914064652952197427172957974915/163258920614834456671948*t^13 - 206172443257750810359478864840845/12558378508833419743996*t^12 + 887108639224000314463510601991285/3139594627208354935999*t^11 - 11147697411809896414815140405547945/3139594627208354935999*t^10 + 102274568420145730000184907766401750/3139594627208354935999*t^9 - 680891586174905234307307310260129050/3139594627208354935999*t^8 + 3250133833241778853761393237120085200/3139594627208354935999*t^7 - 10917098865285820125429030710534744400/3139594627208354935999*t^6 + 25100596446793797842105211883217152800/3139594627208354935999*t^5 - 37894004174840920697182174222465980000/3139594627208354935999*t^4 + 35153031770852452099134652443607632000/3139594627208354935999*t^3 - 17858498989302897488528946759990288000/3139594627208354935999*t^2 + 3963441778166922108693303634043616000/3139594627208354935999*t - 216803075457957591128838492593952000/3139594627208354935999
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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: 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
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The nodes are:
| (0.078547841829282766033 + 3.3796571699537392664e-263j)  +/-  (4.41e-127, 4.41e-127j)
| (44.247984490877309129 + 1.7389281657433774987e-262j)  +/-  (1.39e-119, 1.39e-119j)
| (25.47793419770920874 + 5.9892523930457128654e-274j)  +/-  (1.48e-118, 1.48e-118j)
| (21.029295345416037319 - 5.0871003814763752435e-287j)  +/-  (1.28e-118, 1.28e-118j)
| (17.175367072754279509 - 2.3055424975617078974e-300j)  +/-  (9.83e-119, 9.83e-119j)
| (8.4266299011605486735 - 1.6475962819133054206e-317j)  +/-  (6.63e-120, 6.63e-120j)
| (30.652994356351972654 - 2.1043092668922727845e-331j)  +/-  (1.04e-118, 1.04e-118j)
| (54.143052310834032163 - 4.4979161538715897604e-341j)  +/-  (1.7e-120, 1.7e-120j)
| (36.771544571354009081 - 3.5156536739107884685e-352j)  +/-  (4.9e-119, 4.9e-119j)
| (10.927703514667962118 + 4.7395041978458329048e-362j)  +/-  (2.29e-119, 2.29e-119j)
| (2.9441287152602119281 - 1.3843627496750225908e-371j)  +/-  (2.68e-121, 2.68e-121j)
| (0.41577455678347908331 + 1.3313912778086479584e-375j)  +/-  (1.84e-125, 1.84e-125j)
| (2.2942803602790417198 - 1.3547129215971840697e-371j)  +/-  (1.62e-121, 1.62e-121j)
| (13.828731932223300963 - 2.3711074032453903608e-371j)  +/-  (5.14e-119, 5.14e-119j)
| (6.2899450829374791969 - 7.761836761524451836e-376j)  +/-  (2.55e-120, 2.55e-120j)
| (2.0367129186515464 + 4.083779487129001242e-380j)  +/-  (7.42e-122, 7.42e-122j)
| (1.0328003823318704877 - 4.4732023843547157954e-383j)  +/-  (6.76e-124, 6.76e-124j)
| (4.4861465382379843287 - 1.2686938916424959314e-378j)  +/-  (5.28e-121, 5.28e-121j)
-------------------------------------------------
The weights are:
| (0.18654102940799189758 + 3.9361981218340907638e-263j)  +/-  (1.85e-40, 1.49e-98j)
| (5.101049585076444885e-19 + 1.1924763726568793451e-274j)  +/-  (3.67e-50, 2.95e-108j)
| (4.120348638964374661e-11 - 3.2029087206342860346e-270j)  +/-  (2.31e-46, 1.86e-104j)
| (3.0440342731215989528e-09 + 4.0331225433895213647e-269j)  +/-  (2.52e-45, 2.03e-103j)
| (1.2465758223531948837e-07 - 3.8687605766312583647e-268j)  +/-  (1.64e-44, 1.32e-102j)
| (0.00050656961177380723564 + 1.0712307893611895473e-265j)  +/-  (1.27e-41, 1.02e-99j)
| (2.7274899188425171954e-13 + 1.8052996147873278783e-271j)  +/-  (2.48e-48, 2e-106j)
| (3.6661263486252016189e-23 - 6.7754221834939432666e-277j)  +/-  (1.03e-53, 8.26e-112j)
| (7.1856949155977491992e-16 - 6.4593319733298132555e-273j)  +/-  (5.32e-50, 4.27e-108j)
| (4.8375849305735653192e-05 - 1.9120961475477061194e-266j)  +/-  (6.92e-45, 5.57e-103j)
| (0.082517463507843206883 - 3.1700943751360687254e-263j)  +/-  (6.91e-42, 5.56e-100j)
| (0.31293485257916508429 - 6.4097309796025415818e-263j)  +/-  (1.4e-40, 1.13e-98j)
| (-0.11701830794701629096 + 1.4640936943579889899e-262j)  +/-  (2.1e-41, 1.69e-99j)
| (3.0742088215619484513e-06 + 2.9747601370347515619e-267j)  +/-  (7.54e-46, 6.06e-104j)
| (0.0036445309209260936271 - 5.5290215077080625794e-265j)  +/-  (2.83e-44, 2.28e-102j)
| (0.23966052172448149812 - 1.3975989661683417363e-262j)  +/-  (3.03e-42, 2.49e-100j)
| (0.27257965841725635477 + 4.7300181483114310718e-263j)  +/-  (7.95e-43, 6.65e-101j)
| (0.01858210397635758796 + 2.9488928736910392392e-264j)  +/-  (7.21e-44, 5.74e-102j)
