Starting with polynomial:
P : 35/8*t^4 - 15/4*t^2 + 3/8
Extension levels are: 4 13
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Trying to find an order 13 Kronrod extension for:
P1 : 35/8*t^4 - 15/4*t^2 + 3/8
Solvable: 1
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Ending with final polynomial:
P : 35/8*t^17 - 20554887/1192364*t^15 + 16554685/596182*t^13 - 43561973/1850220*t^11 + 927511585/82273116*t^9 - 83298215/27424372*t^7 + 1686197513/3907973010*t^5 - 14357343/521063068*t^3 + 2723149/5210630680*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
  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:
| (0.98889990878051281863 - 5.9824040038963398829e-436j)  +/-  (3.53e-123, 3.53e-123j)
| (-0.94220752437321014121 - 1.088676021903592685e-441j)  +/-  (6.73e-123, 6.73e-123j)
| (-0.86113631159405257522 + 7.5651192066955151955e-446j)  +/-  (5.13e-123, 5.13e-123j)
| (-0.98889990878051281863 + 2.3903295129693981925e-448j)  +/-  (3.46e-123, 3.46e-123j)
| (0.94220752437321014121 - 5.627310090074522157e-446j)  +/-  (6.48e-123, 6.48e-123j)
| (0.75122694779756385225 - 4.5000266450334969191e-453j)  +/-  (2.51e-123, 2.51e-123j)
| (-0.17687947303552314887 + 1.7624465723003866185e-463j)  +/-  (9.2e-127, 9.2e-127j)
| (-0.75122694779756385225 - 2.2640086611545119544e-472j)  +/-  (2.5e-123, 2.5e-123j)
| (-0.3399810435848562648 - 3.987187697981515321e-478j)  +/-  (1.47e-125, 1.47e-125j)
| (0.3399810435848562648 - 7.1656815096664118768e-484j)  +/-  (1.47e-125, 1.47e-125j)
| (0.86113631159405257522 + 1.6364287392998134215e-493j)  +/-  (5.48e-123, 5.48e-123j)
| (0.17687947303552314887 - 6.1685692711887498114e-494j)  +/-  (9.2e-127, 9.2e-127j)
| (-0.48484586606682079734 - 3.6436108648472408213e-493j)  +/-  (1.18e-124, 1.18e-124j)
| (-0.62190453863441120775 - 5.8889061565623168537e-494j)  +/-  (6.7e-124, 6.7e-124j)
| (-9.3137805138981690401e-496 - 2.7766552095052986522e-495j)  +/-  (4.98e-494, 4.98e-494j)
| (0.62190453863441120775 - 8.6296046799013598398e-495j)  +/-  (7.26e-124, 7.26e-124j)
| (0.48484586606682079734 + 1.0715927531199355721e-502j)  +/-  (1.21e-124, 1.21e-124j)
-------------------------------------------------
The weights are:
| (0.028408146158246043921 + 7.9862414571762055692e-436j)  +/-  (1.29e-46, 2.06e-106j)
| (0.06454418839474040326 - 3.3226885157767609205e-437j)  +/-  (6.23e-47, 9.94e-107j)
| (0.096693990378749456004 + 7.8240791489004751848e-437j)  +/-  (3.56e-47, 5.68e-107j)
| (0.028408146158246043921 + 8.5924329690443350285e-438j)  +/-  (2.51e-47, 4e-107j)
| (0.06454418839474040326 - 1.3741691678735576569e-435j)  +/-  (2.44e-48, 3.9e-108j)
| (0.12156658151794761728 - 1.1809564151086894939e-435j)  +/-  (6.51e-49, 1.04e-108j)
| (0.17202573308373732268 - 7.6806747640292895313e-436j)  +/-  (9.99e-49, 1.59e-108j)
| (0.12156658151794761728 - 1.613009791488574559e-436j)  +/-  (1.22e-48, 1.95e-108j)
| (0.15311364210121624058 + 6.6916070123733238992e-436j)  +/-  (7.28e-49, 1.16e-108j)
| (0.15311364210121624058 + 1.3703304088241933435e-435j)  +/-  (6.51e-50, 1.04e-109j)
| (0.096693990378749456004 + 1.1329102748340395796e-435j)  +/-  (5.88e-50, 9.37e-110j)
| (0.17202573308373732268 - 1.1026772310540914705e-435j)  +/-  (5.85e-50, 9.34e-110j)
| (0.1391299850682844768 - 5.0755796527930221392e-436j)  +/-  (5.34e-50, 8.52e-110j)
| (0.1348563472342619652 + 3.0894699268122573017e-436j)  +/-  (2.94e-50, 4.69e-110j)
| (0.17932277212563294855 + 8.8912297266284176937e-436j)  +/-  (3.07e-50, 4.9e-110j)
| (0.1348563472342619652 + 1.3560132285760250269e-435j)  +/-  (2.13e-51, 3.4e-111j)
| (0.1391299850682844768 - 1.4839858289661326296e-435j)  +/-  (3.3e-51, 5.23e-111j)
