Starting with polynomial:
P : 16*t^4 - 48*t^2 + 12
Extension levels are: 4 20
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Trying to find an order 20 Kronrod extension for:
P1 : 16*t^4 - 48*t^2 + 12
Solvable: 1
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Ending with final polynomial:
P : 16*t^24 - 673109229408/363937411*t^22 + 32020783562037/363937411*t^20 - 818664521682555/363937411*t^18 + 2902354334703135/85632332*t^16 - 6654160856955555/21408083*t^14 + 296858052476011845/171264664*t^12 - 979371031782448305/171264664*t^10 + 7231298316318101025/685058656*t^8 - 3409934485088456325/342529328*t^6 + 23115246943434671025/5480469248*t^4 - 3840059178024144075/5480469248*t^2 + 36936160291505475/1289522176
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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
Positive weights:   22 out of 24
Indefinite weights: 0 out of 24
Negative weights:   2 out of 24
Extension rule has valid weights: 0
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*** EXTENSION WITH INVALID WEIGHTS ***
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