Starting with polynomial:
P : 4*t^2 - 2
Extension levels are: 2 3 14
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Trying to find an order 3 Kronrod extension for:
P1 : 4*t^2 - 2
Solvable: 1
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Trying to find an order 14 Kronrod extension for:
P2 : 4*t^5 - 14*t^3 + 6*t
Solvable: 1
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Ending with final polynomial:
P : 4*t^19 - 29110357381/101992554*t^17 + 1619951720893/203985108*t^15 - 15088279415755/135990072*t^13 + 227384524996265/271980144*t^11 - 1848310702373135/543960288*t^9 + 851785811281405/120880064*t^7 - 1578667637211665/241760128*t^5 + 958190018560775/483520256*t^3 - 24793868073975/483520256*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
Positive weights:   18 out of 19
Indefinite weights: 0 out of 19
Negative weights:   1 out of 19
Extension rule has valid weights: 0
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*** EXTENSION WITH INVALID WEIGHTS ***
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