Starting with polynomial:
P : t^7 - 21*t^5 + 105*t^3 - 105*t
Extension levels are: 7 16
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Trying to find an order 16 Kronrod extension for:
P1 : t^7 - 21*t^5 + 105*t^3 - 105*t
Solvable: 1
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Ending with final polynomial:
P : t^23 - 21735/83*t^21 + 577181955/20999*t^19 - 159660594807/104995*t^17 + 5130674653902/104995*t^15 - 19860111961326/20999*t^13 + 21101868409986/1909*t^11 - 145384923763170/1909*t^9 + 6739282250883/23*t^7 - 1088702779003749/1909*t^5 + 889027794718245/1909*t^3 - 8514428328315/83*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
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The nodes are:
| (5.3194193963983496711 - 6.2297352626527142191e-454j)  +/-  (2.58e-122, 2.58e-122j)
| (-6.2149642472446808216 - 1.640898532831394438e-464j)  +/-  (1.96e-122, 1.96e-122j)
| (6.2149642472446808216 + 9.0372416039736988416e-476j)  +/-  (2.14e-122, 2.14e-122j)
| (9.3919552615960244778 + 8.9013344902764635084e-486j)  +/-  (1.02e-123, 1.02e-123j)
| (-5.3194193963983496711 - 1.3928443577405490339e-486j)  +/-  (2.74e-122, 2.74e-122j)
| (-7.2682295904893190985 + 6.2502833374936606913e-497j)  +/-  (8.73e-123, 8.73e-123j)
| (7.2682295904893190985 - 1.5795181928298684117e-498j)  +/-  (8.88e-123, 8.88e-123j)
| (-2.3667594107345412886 - 1.6513311002460623518e-497j)  +/-  (1.22e-123, 1.22e-123j)
| (-9.3919552615960244778 - 5.2427080117085559013e-499j)  +/-  (1.23e-123, 1.23e-123j)
| (1.1544053947399681272 - 1.2273308999066995419e-500j)  +/-  (3.91e-125, 3.91e-125j)
| (2.3667594107345412886 + 1.9717306657406814527e-501j)  +/-  (1.27e-123, 1.27e-123j)
| (-3.0377657228151619173 + 5.079818293019192397e-497j)  +/-  (4.45e-123, 4.45e-123j)
| (-3.7504397177257422563 + 3.7529559531489299148e-501j)  +/-  (1.11e-122, 1.11e-122j)
| (-1.7405731099688700502 - 4.4998523812653544533e-505j)  +/-  (2.7e-124, 2.7e-124j)
| (3.0377657228151619173 + 9.8006087212427440867e-503j)  +/-  (4.32e-123, 4.32e-123j)
| (0.58118078007696595791 + 1.4931832105347477355e-508j)  +/-  (4.15e-126, 4.15e-126j)
| (3.7504397177257422563 + 9.6072429716291966848e-506j)  +/-  (1.08e-122, 1.08e-122j)
| (-0.58118078007696595791 - 4.5420021613224265719e-510j)  +/-  (4.15e-126, 4.15e-126j)
| (-1.1544053947399681272 - 4.1019957019443164977e-509j)  +/-  (3.56e-125, 3.56e-125j)
| (4.5071160532357457395 - 4.8258772964050782326e-510j)  +/-  (2.56e-122, 2.56e-122j)
| (-4.5071160532357457395 - 9.3423750510599228193e-512j)  +/-  (2.03e-122, 2.03e-122j)
| (1.7405731099688700502 + 1.2909146566137299521e-523j)  +/-  (2.72e-124, 2.72e-124j)
| (-6.3341607480340741058e-579 - 3.2390594734265151677e-580j)  +/-  (1.46e-577, 1.46e-577j)
-------------------------------------------------
The weights are:
| (2.4237307218511324976e-07 + 4.445344486714477917e-460j)  +/-  (8.88e-47, 3.69e-107j)
| (1.5599401632730995707e-09 - 8.4447920685672574196e-463j)  +/-  (4.35e-49, 1.81e-109j)
| (1.5599401632730995707e-09 + 1.0876671493092150864e-461j)  +/-  (1.66e-48, 6.9e-109j)
| (7.2607741122400220458e-19 + 7.5313280944847156182e-467j)  +/-  (5.57e-53, 2.32e-113j)
| (2.4237307218511324976e-07 + 1.419252706017633913e-461j)  +/-  (2.09e-48, 8.69e-109j)
| (1.6083940125257157291e-12 + 2.1214195341677579908e-464j)  +/-  (2.76e-51, 1.15e-111j)
| (1.6083940125257157291e-12 - 1.3702557864192129451e-463j)  +/-  (4.35e-51, 1.81e-111j)
| (0.015736950022609488281 + 1.8484004970817634713e-458j)  +/-  (2.46e-44, 1.02e-104j)
| (7.2607741122400220458e-19 - 2.084890398759593307e-467j)  +/-  (2.37e-54, 9.86e-115j)
| (0.11760800533101336774 + 1.7685285362228723204e-457j)  +/-  (3.07e-41, 1.28e-101j)
| (0.015736950022609488281 + 4.8116399438752240456e-458j)  +/-  (1.88e-45, 7.8e-106j)
| (0.0027367613267684886502 - 4.8209969156628875373e-459j)  +/-  (2.05e-46, 8.51e-107j)
| (0.00025824112391977786834 + 9.6020694071807015592e-460j)  +/-  (1.25e-47, 5.18e-108j)
| (0.052934251247557575001 - 5.357817827474719937e-458j)  +/-  (1.36e-44, 5.64e-105j)
| (0.0027367613267684886502 - 1.7658229270100830953e-458j)  +/-  (5.87e-48, 2.43e-108j)
| (0.19424066112588019747 - 2.2362425800141106408e-457j)  +/-  (6e-45, 2.51e-105j)
| (0.00025824112391977786834 + 5.5507039326375100679e-459j)  +/-  (3.06e-49, 1.27e-109j)
| (0.19424066112588019747 - 1.7957242706154905604e-457j)  +/-  (5.31e-46, 2.3e-106j)
| (0.11760800533101336774 + 1.1378043665619972743e-457j)  +/-  (4.19e-46, 1.77e-106j)
| (1.2098830641565390763e-05 - 1.7077288110293641421e-459j)  +/-  (3.32e-50, 1.38e-110j)
| (1.2098830641565390763e-05 - 1.4116814919612422784e-460j)  +/-  (3.71e-50, 1.67e-110j)
| (0.052934251247557575001 - 1.0569370876802380567e-457j)  +/-  (1.99e-47, 7.54e-108j)
| (0.23294557411397759294 + 2.2258344627920898088e-457j)  +/-  (6.81e-47, 4.07e-107j)
