Starting with polynomial:
P : t^4 - 6*t^2 + 3
Extension levels are: 4 5 10
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Trying to find an order 5 Kronrod extension for:
P1 : t^4 - 6*t^2 + 3
Solvable: 1
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Trying to find an order 10 Kronrod extension for:
P2 : t^9 - 21*t^7 + 108*t^5 - 135*t^3 + 45*t
Solvable: 1
-------------------------------------------------
Ending with final polynomial:
P : t^19 - 8377498086/68215861*t^17 + 57601919589/9745123*t^15 - 9837542257155/68215861*t^13 + 131441284093635/68215861*t^11 - 970062879190185/68215861*t^9 + 543834376395255/9745123*t^7 - 1045646903415015/9745123*t^5 + 867789327309300/9745123*t^3 - 239747148335475/9745123*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:
| (2.3344142183389772393 - 3.7431367075362894902e-294j)  +/-  (4.39e-124, 4.39e-124j)
| (6.4605144082402146964 - 1.4465586086799892624e-300j)  +/-  (5.46e-124, 5.46e-124j)
| (-5.3342504636618002739 + 1.1570384064237447192e-305j)  +/-  (2.54e-123, 2.54e-123j)
| (-2.3344142183389772393 + 3.2753087197226004359e-305j)  +/-  (5.03e-124, 5.03e-124j)
| (5.3342504636618002739 + 5.1599311713901641256e-315j)  +/-  (2.5e-123, 2.5e-123j)
| (-4.4397138267678565547 + 1.0064356036347414192e-326j)  +/-  (4.03e-123, 4.03e-123j)
| (4.4397138267678565547 - 4.0546824276549369765e-336j)  +/-  (4.54e-123, 4.54e-123j)
| (-1.5738770477342024144 - 2.2109670425048792472e-344j)  +/-  (1.03e-124, 1.03e-124j)
| (-0.74196378430272585765 - 1.7995064845762447876e-343j)  +/-  (8.33e-126, 8.33e-126j)
| (1.0379709584894152952 + 6.896500710216236099e-348j)  +/-  (3.18e-125, 3.18e-125j)
| (0.74196378430272585765 + 2.5691467189104244482e-355j)  +/-  (8.33e-126, 8.33e-126j)
| (-3.0705100502673370573 + 9.2849081363400466892e-357j)  +/-  (1.76e-123, 1.76e-123j)
| (-3.7313022243357029508 - 5.0955740506363896643e-365j)  +/-  (4.46e-123, 4.46e-123j)
| (2.9315571143349318542e-372 + 1.4195603143738971817e-372j)  +/-  (6.19e-371, 6.19e-371j)
| (3.0705100502673370573 + 3.3724278121252489453e-383j)  +/-  (1.65e-123, 1.65e-123j)
| (1.5738770477342024144 - 1.5893957375505591599e-399j)  +/-  (9.75e-125, 9.75e-125j)
| (3.7313022243357029508 + 3.5702100460050802484e-411j)  +/-  (4.27e-123, 4.27e-123j)
| (-6.4605144082402146964 - 2.0284412067549053027e-420j)  +/-  (5.46e-124, 5.46e-124j)
| (-1.0379709584894152952 + 1.3270703886063550839e-421j)  +/-  (3.08e-125, 3.08e-125j)
-------------------------------------------------
The weights are:
| (0.019851601279214062947 + 1.375186296571639221e-295j)  +/-  (1.33e-45, 2.19e-107j)
| (4.5014149534841966772e-10 + 9.575119209270155193e-302j)  +/-  (8.87e-54, 1.46e-115j)
| (2.6269870042079918018e-07 + 3.2346729508373829992e-300j)  +/-  (4.99e-53, 8.2e-115j)
| (0.019851601279214062947 + 1.5915611036050613451e-296j)  +/-  (1.72e-47, 2.84e-109j)
| (2.6269870042079918018e-07 - 8.2689921459701321934e-300j)  +/-  (8.03e-53, 1.32e-114j)
| (1.6669721329231728817e-05 - 7.7033923458030540347e-299j)  +/-  (5.3e-52, 8.72e-114j)
| (1.6669721329231728817e-05 + 2.4786859821553475752e-298j)  +/-  (5.74e-52, 9.45e-114j)
| (0.086685768409641819651 - 9.5353487906604990284e-296j)  +/-  (6.52e-47, 1.07e-108j)
| (0.2052546869406181111 - 4.6998263646836651257e-295j)  +/-  (1.99e-45, 3.28e-107j)
| (0.034093121772176221711 + 1.0326114448424178915e-294j)  +/-  (8.9e-46, 1.46e-107j)
| (0.2052546869406181111 - 9.0793673315561724929e-295j)  +/-  (1.03e-45, 1.69e-107j)
| (0.002506335323354266339 - 3.4859608142171537168e-297j)  +/-  (2.6e-50, 4.27e-112j)
| (0.00024409756828314798386 + 6.994181773732907871e-298j)  +/-  (2.6e-51, 4.28e-113j)
| (0.30269491167308244479 + 3.6033052700649167995e-295j)  +/-  (1.39e-47, 2.28e-109j)
| (0.002506335323354266339 + 2.559633326594097907e-296j)  +/-  (1.83e-51, 3.01e-113j)
| (0.086685768409641819651 - 4.9000787675595006547e-295j)  +/-  (1.38e-49, 2.28e-111j)
| (0.00024409756828314798386 - 3.0370883911073080761e-297j)  +/-  (2.72e-52, 4.47e-114j)
| (4.5014149534841966772e-10 - 4.4921228759097506923e-302j)  +/-  (7.54e-57, 1.26e-118j)
| (0.034093121772176221711 + 3.9696596832089919752e-295j)  +/-  (6.06e-50, 9.03e-112j)
