Starting with polynomial:
P : t
Extension levels are: 1 4 16
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Trying to find an order 4 Kronrod extension for:
P1 : t
Solvable: 1
-------------------------------------------------
Trying to find an order 16 Kronrod extension for:
P2 : t^5 - 10/9*t^3 + 5/21*t
Solvable: 1
-------------------------------------------------
Ending with final polynomial:
P : t^21 - 35335620166/7135347843*t^19 + 180709480704313/17231865040845*t^17 - 96664607452792/7789747210245*t^15 + 1734603690026/192752697357*t^13 - 41778582658804/10122121377423*t^11 + 37797535859134/31699057228983*t^9 - 534118021610248/2553535165668075*t^7 + 1205860438533401/58731308810365725*t^5 - 234576601175962/246671497003536045*t^3 + 1112587844447/82223832334512015*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
-------------------------------------------------
The nodes are:
| (-0.99261540453781165524 + 4.6307552318705935647e-363j)  +/-  (7.65e-122, 7.65e-122j)
| (0.15500602137286204479 + 1.1155222403652014737e-366j)  +/-  (9.8e-127, 9.8e-127j)
| (-0.96134856368178933391 + 3.7139902363594142355e-367j)  +/-  (1.78e-121, 1.78e-121j)
| (-0.63087264370021210705 - 5.1808999520062221908e-371j)  +/-  (1.37e-122, 1.37e-122j)
| (0.63087264370021210705 - 8.9577505557189334966e-373j)  +/-  (1.67e-122, 1.67e-122j)
| (0.9061798459386639928 - 8.4593498067882988895e-377j)  +/-  (1.83e-121, 1.83e-121j)
| (0.99261540453781165524 - 1.7229128692049680614e-376j)  +/-  (8.19e-122, 8.19e-122j)
| (-0.9061798459386639928 - 1.3341086625370475996e-382j)  +/-  (1.76e-121, 1.76e-121j)
| (-0.82914919218009739841 + 9.0029365461312359914e-383j)  +/-  (1.14e-121, 1.14e-121j)
| (0.96134856368178933391 - 4.0529424299694115369e-381j)  +/-  (1.94e-121, 1.94e-121j)
| (0.73415620079730241944 + 8.2931357088396748641e-391j)  +/-  (4.66e-122, 4.66e-122j)
| (0.43678909447140196308 - 2.4619237118108597285e-407j)  +/-  (5.47e-124, 5.47e-124j)
| (-0.43678909447140196308 - 2.8966411927343702829e-413j)  +/-  (5.16e-124, 5.16e-124j)
| (-0.53846931010568309104 + 1.263353878886310141e-414j)  +/-  (4.06e-123, 4.06e-123j)
| (-2.1501077771580521754e-424 + 2.013014440880786931e-424j)  +/-  (6.19e-423, 6.19e-423j)
| (0.82914919218009739841 + 1.2100187841118109338e-447j)  +/-  (1.12e-121, 1.12e-121j)
| (0.53846931010568309104 + 1.1529901815270508667e-468j)  +/-  (4.12e-123, 4.12e-123j)
| (-0.15500602137286204479 - 9.3169924809060842216e-477j)  +/-  (9.8e-127, 9.8e-127j)
| (-0.73415620079730241944 - 1.4279371440080919692e-474j)  +/-  (4.97e-122, 4.97e-122j)
| (-0.30384202795433928862 + 2.6031153763229860586e-476j)  +/-  (2.37e-125, 2.37e-125j)
| (0.30384202795433928862 + 3.8546424672688284579e-482j)  +/-  (2.63e-125, 2.63e-125j)
-------------------------------------------------
The weights are:
| (0.018922109385135370112 + 6.1547220860272651999e-363j)  +/-  (7.65e-44, 1.74e-102j)
| (0.15306752425759946796 - 4.353534747564966562e-363j)  +/-  (1.95e-44, 4.43e-103j)
| (0.043459331297916842016 - 1.054099504738182995e-362j)  +/-  (3.38e-44, 7.69e-103j)
| (0.10072124042701687241 - 1.6291191237767933226e-362j)  +/-  (7.7e-45, 1.75e-103j)
| (0.10072124042701687241 - 3.6295076725151218979e-363j)  +/-  (7.38e-45, 1.68e-103j)
| (0.066547042293159185718 + 3.9130088855767842971e-364j)  +/-  (1.59e-45, 3.62e-104j)
| (0.018922109385135370112 + 4.413199712241777462e-365j)  +/-  (3.14e-46, 7.13e-105j)
| (0.066547042293159185718 + 8.5965373863070956756e-363j)  +/-  (3.43e-45, 7.79e-104j)
| (0.086910938227872853106 - 9.0267086343381314393e-363j)  +/-  (1.44e-45, 3.28e-104j)
| (0.043459331297916842016 - 1.6865586624789984169e-364j)  +/-  (5.56e-46, 1.26e-104j)
| (0.10167688509672312588 + 1.6991876686199728174e-363j)  +/-  (5.5e-46, 1.25e-104j)
| (0.11939367874949361918 - 5.4803318001784291186e-363j)  +/-  (1.67e-46, 3.81e-105j)
| (0.11939367874949361918 - 1.4096501473939213921e-362j)  +/-  (3.31e-47, 7.53e-106j)
| (0.088182950460129579541 + 1.863082534157443045e-362j)  +/-  (6.09e-47, 1.38e-105j)
| (0.15595958025586339571 + 4.7719945621789988158e-363j)  +/-  (6.6e-48, 1.5e-106j)
| (0.086910938227872853106 - 8.0989226499569577605e-364j)  +/-  (1.15e-47, 2.61e-106j)
| (0.088182950460129579541 + 5.5253602727957697054e-363j)  +/-  (1.33e-47, 3.02e-106j)
| (0.15306752425759946796 - 5.9655890005288031859e-363j)  +/-  (1.48e-48, 3.4e-107j)
| (0.10167688509672312588 + 1.1353513385757272282e-362j)  +/-  (6.97e-49, 1.59e-107j)
| (0.14313850967702138623 + 8.6182693750862044315e-363j)  +/-  (8.64e-49, 1.98e-107j)
| (0.14313850967702138623 + 4.5770647814309193363e-363j)  +/-  (7.1e-49, 1.53e-107j)
