Starting with polynomial:
P : 8*t^3 - 12*t
Extension levels are: 3 6 14
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Trying to find an order 6 Kronrod extension for:
P1 : 8*t^3 - 12*t
Solvable: 1
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Trying to find an order 14 Kronrod extension for:
P2 : 8*t^9 - 117*t^7 + 945/2*t^5 - 2205/4*t^3 + 945/8*t
Solvable: 1
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Ending with final polynomial:
P : 8*t^23 - 3852927458237/5101506975*t^21 + 200673176311657/6802009300*t^19 - 8516201417318679/13604018600*t^17 + 86648979975626579/10883214880*t^15 - 274821978930204615/4353285952*t^13 + 2738115730067306589/8706571904*t^11 - 84416696594777760213/87065719040*t^9 + 310835630853592445601/174131438080*t^7 - 128055455760565021689/69652575232*t^5 + 127735463726273808405/139305150464*t^3 - 40420437771237240717/278610300928*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:   19 out of 23
Indefinite weights: 0 out of 23
Negative weights:   4 out of 23
Extension rule has valid weights: 0
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*** EXTENSION WITH INVALID WEIGHTS ***
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