Starting with polynomial:
P : 16*t^4 - 48*t^2 + 12
Extension levels are: 4 5 14
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Trying to find an order 5 Kronrod extension for:
P1 : 16*t^4 - 48*t^2 + 12
Solvable: 1
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Trying to find an order 14 Kronrod extension for:
P2 : 16*t^9 - 168*t^7 + 432*t^5 - 270*t^3 + 45*t
Solvable: 1
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Ending with final polynomial:
P : 16*t^23 - 1297379011493152/910428501785*t^21 + 46587422190452784/910428501785*t^19 - 878796263976985038/910428501785*t^17 + 9529093728525786696/910428501785*t^15 - 12254430548564146215/182085700357*t^13 + 8497918703745057951/33106490974*t^11 - 9412546414531352274/16553245487*t^9 + 186327422204203087353/264851927792*t^7 - 121470447834989743581/264851927792*t^5 + 76217320752581838375/529703855584*t^3 - 35261234801507861055/2118815422336*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:   21 out of 23
Indefinite weights: 0 out of 23
Negative weights:   2 out of 23
Extension rule has valid weights: 0
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*** EXTENSION WITH INVALID WEIGHTS ***
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