Starting with polynomial:
P : 16*t^4 - 48*t^2 + 12
Extension levels are: 4 10 19
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Trying to find an order 10 Kronrod extension for:
P1 : 16*t^4 - 48*t^2 + 12
Solvable: 1
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Trying to find an order 19 Kronrod extension for:
P2 : 16*t^14 - 3816/7*t^12 + 44964/7*t^10 - 225630/7*t^8 + 68715*t^6 - 108945/2*t^4 + 46845/4*t^2 - 2835/8
Solvable: 1
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Ending with final polynomial:
P : 16*t^33 - 6978881355496824168728920184/2495856217653108003195383*t^31 + 2635754801841352274187490948572/12479281088265540015976915*t^29 - 1249919337187246528948724165848686/137272091970920940175746065*t^27 + 34219750611530818721219158999289259/137272091970920940175746065*t^25 - 250654077180855141828633011491865145/54908836788368376070298426*t^23 + 900308297364693042806082770570484435/15688239082390964591513836*t^21 - 15704757515709116263320063828337714977/31376478164781929183027672*t^19 + 189898734204661971894897774788765528067/62752956329563858366055344*t^17 - 143093424272692843545447606337655841771/11409628423557065157464608*t^15 + 8743611889380386209892869759276280665485/251011825318255433464221376*t^13 - 31339865344802557315448172883482762568695/502023650636510866928442752*t^11 + 6194946759310778915531538349515120163545/91277027388456521259716864*t^9 - 7387845987458637803702228754706664432895/182554054776913042519433728*t^7 + 4141897815661356296102379763005147426435/365108109553826085038867456*t^5 - 937953319370154974082928714110788757825/730216219107652170077734912*t^3 + 24340633132581997593423752999883945825/730216219107652170077734912*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:   28 out of 33
Indefinite weights: 0 out of 33
Negative weights:   5 out of 33
Extension rule has valid weights: 0
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*** EXTENSION WITH INVALID WEIGHTS ***
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