Starting with polynomial:
P : 4*t^2 - 2
Extension levels are: 2 3 16
-------------------------------------------------
Trying to find an order 3 Kronrod extension for:
P1 : 4*t^2 - 2
Solvable: 1
-------------------------------------------------
Trying to find an order 16 Kronrod extension for:
P2 : 4*t^5 - 14*t^3 + 6*t
Solvable: 1
-------------------------------------------------
Ending with final polynomial:
P : 4*t^21 - 12543714801014/32881952901*t^19 + 206152459514434/14092265529*t^17 - 28881725524174430/98645858703*t^15 + 31226480962750505/9394843686*t^13 - 409654075630178275/18789687372*t^11 + 378991898032014410/4697421843*t^9 - 1967747357667227565/12526458248*t^7 + 13918253031092263425/100211665984*t^5 - 7842371094515732775/200423331968*t^3 + 13498352903596275/200423331968*t
-------------------------------------------------
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:   20 out of 21
Indefinite weights: 0 out of 21
Negative weights:   1 out of 21
Extension rule has valid weights: 0
**************************************
*** EXTENSION WITH INVALID WEIGHTS ***
**************************************
