Starting with polynomial:
P : t^8 - 28*t^6 + 210*t^4 - 420*t^2 + 105
Extension levels are: 8 15
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Trying to find an order 15 Kronrod extension for:
P1 : t^8 - 28*t^6 + 210*t^4 - 420*t^2 + 105
Solvable: 1
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Ending with final polynomial:
P : t^23 - 226513/1105*t^21 + 19046601/1105*t^19 - 858410581/1105*t^17 + 4552011002/221*t^15 - 73444706538/221*t^13 + 55544111994/17*t^11 - 324675714594/17*t^9 + 1069116542109/17*t^7 - 1796386301325/17*t^5 + 1274070981645/17*t^3 - 242579663865/17*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: 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
Positive weights:   23 out of 23
Indefinite weights: 0 out of 23
Negative weights:   0 out of 23
Extension rule has valid weights: 1
-------------------------------------------------
The nodes are:
| (-2.2020092436456178225 + 2.3744330597241635159e-266j)  +/-  (1.37e-123, 1.37e-123j)
| (3.4495913081165000773 - 3.2727955678117655604e-267j)  +/-  (1.34e-122, 1.34e-122j)
| (-7.6853322799238771702 - 7.8064185106563868704e-274j)  +/-  (3.49e-123, 3.49e-123j)
| (-3.4495913081165000773 + 1.1624685200987588435e-273j)  +/-  (1.25e-122, 1.25e-122j)
| (6.6026855332354176536 + 1.0715633815133628364e-272j)  +/-  (1.53e-122, 1.53e-122j)
| (7.6853322799238771702 - 2.0052818384240660574e-278j)  +/-  (3.65e-123, 3.65e-123j)
| (5.6997098857076010682 + 1.6291005073236486495e-282j)  +/-  (3.23e-122, 3.23e-122j)
| (-6.6026855332354176536 + 4.1664781296749035643e-291j)  +/-  (1.76e-122, 1.76e-122j)
| (-5.6997098857076010682 + 7.7943360125973956944e-291j)  +/-  (3e-122, 3e-122j)
| (1.6365190424351079992 - 4.8832031818577998839e-293j)  +/-  (2.36e-124, 2.36e-124j)
| (2.8024858612875416991 + 1.1204137776296637824e-309j)  +/-  (4.99e-123, 4.99e-123j)
| (-4.1445471861258943321 + 2.2735418824676642223e-319j)  +/-  (2.64e-122, 2.64e-122j)
| (-2.8024858612875416991 - 1.7829841027118905286e-319j)  +/-  (4.82e-123, 4.82e-123j)
| (-1.6365190424351079992 + 4.5722811128732320184e-319j)  +/-  (2.39e-124, 2.39e-124j)
| (1.085007946272912263 - 4.7042383271017127009e-326j)  +/-  (2.85e-125, 2.85e-125j)
| (4.1445471861258943321 - 2.6151530693139967287e-344j)  +/-  (2.77e-122, 2.77e-122j)
| (-2.6018557627854414261e-359 - 2.0443152421885611205e-359j)  +/-  (7.61e-358, 7.61e-358j)
| (-0.53907981135137510807 + 1.7655449818901209677e-358j)  +/-  (2.66e-126, 2.66e-126j)
| (-1.085007946272912263 - 1.7241650213770712575e-361j)  +/-  (3.41e-125, 3.41e-125j)
| (4.8904899387500053878 + 8.6357777781569078401e-367j)  +/-  (3.4e-122, 3.4e-122j)
| (2.2020092436456178225 - 4.6458104353128079009e-379j)  +/-  (1.41e-123, 1.41e-123j)
| (0.53907981135137510807 - 4.5402450260153138804e-389j)  +/-  (2.87e-126, 2.87e-126j)
| (-4.8904899387500053878 - 1.2140917577134794938e-390j)  +/-  (3.44e-122, 3.44e-122j)
-------------------------------------------------
The weights are:
| (0.020472389386045783163 + 9.0200573074992073728e-268j)  +/-  (4.86e-37, 4.85e-98j)
| (0.00069766587596080276026 + 1.1524167403693131998e-269j)  +/-  (7.7e-42, 7.68e-103j)
| (7.4215619726477663232e-14 + 4.8547233812302308823e-276j)  +/-  (1.55e-49, 1.54e-110j)
| (0.00069766587596080276026 - 2.5766257912681838738e-269j)  +/-  (6.16e-42, 6.15e-103j)
| (1.3204411234998099479e-10 + 1.7601463751345894684e-274j)  +/-  (1.23e-48, 1.23e-109j)
| (7.4215619726477663232e-14 - 2.3321338207953379322e-276j)  +/-  (2.51e-50, 2.5e-111j)
| (2.9869990507723361737e-08 - 4.4568347610284926471e-273j)  +/-  (1.38e-47, 1.37e-108j)
| (1.3204411234998099479e-10 - 4.2447654823374083966e-274j)  +/-  (9.27e-50, 9.25e-111j)
| (2.9869990507723361737e-08 + 1.3000194042320418203e-272j)  +/-  (9.66e-49, 9.63e-110j)
| (0.058071460617050659648 - 3.5181954390813887175e-268j)  +/-  (6.81e-42, 6.78e-103j)
| (0.0048984195621685112186 - 4.5287392438687642356e-269j)  +/-  (1.25e-44, 1.25e-105j)
| (5.343793164142848145e-05 + 2.6859567350668367341e-270j)  +/-  (6.06e-47, 6.04e-108j)
| (0.0048984195621685112186 + 2.4306384841167362037e-268j)  +/-  (8.55e-45, 8.5e-106j)
| (0.058071460617050659648 - 2.0956141884000666275e-267j)  +/-  (3.44e-43, 3.42e-104j)
| (0.12155267067381994966 + 7.1775664329141908812e-268j)  +/-  (1.04e-42, 1.03e-103j)
| (5.343793164142848145e-05 - 3.0099087517553214896e-271j)  +/-  (5.63e-48, 5.6e-109j)
| (0.21432921131368011315 + 1.6466679320587164127e-267j)  +/-  (4.87e-43, 4.83e-104j)
| (0.18708734136102960663 - 1.9038986919874239343e-267j)  +/-  (3.02e-43, 3e-104j)
| (0.12155267067381994966 + 1.9577812722469165037e-267j)  +/-  (1.2e-43, 1.2e-104j)
| (1.9789333343661741194e-06 + 5.6970620506820538087e-272j)  +/-  (4.72e-49, 4.7e-110j)
| (0.020472389386045783163 + 1.377023326570007588e-268j)  +/-  (8.69e-46, 8.49e-107j)
| (0.18708734136102960663 - 1.1963417479990736137e-267j)  +/-  (1.06e-44, 9.9e-106j)
| (1.9789333343661741194e-06 - 2.2433807362598186946e-271j)  +/-  (3.34e-49, 3.45e-110j)
