Starting with polynomial:
P : 32768*t^15 - 1720320*t^13 + 33546240*t^11 - 307507200*t^9 + 1383782400*t^7 - 2905943040*t^5 + 2421619200*t^3 - 518918400*t
Extension levels are: 15 26
-------------------------------------------------
Trying to find an order 26 Kronrod extension for:
P1 : 32768*t^15 - 1720320*t^13 + 33546240*t^11 - 307507200*t^9 + 1383782400*t^7 - 2905943040*t^5 + 2421619200*t^3 - 518918400*t
Solvable: 1
-------------------------------------------------
Ending with final polynomial:
P : 32768*t^41 - 187048718344192/14887773*t^39 + 176261273330102272/84364047*t^37 - 17006673514769868800/84364047*t^35 + 3211284238924532126720/253092141*t^33 - 46732854643806961710080/84364047*t^31 + 162959186945857243701760/9373783*t^29 - 33801073149374097718511360/84364047*t^27 + 64339187076981061355510400/9373783*t^25 - 823766293712022628679712000/9373783*t^23 + 7882594806430278838984080000/9373783*t^21 - 2952222418973388706465320000/493357*t^19 + 909742572018786339083250000/29021*t^17 - 3453227038204551179574502500/29021*t^15 + 9281051685315441484909706250/29021*t^13 - 17091847151835262339835176875/29021*t^11 + 20577857007007650628311783750/29021*t^9 - 120914547492846549612221926875/232168*t^7 + 97380998467467210486349734375/464336*t^5 - 35895439572223163460743840625/928672*t^3 + 4080072969924076582065984375/1857344*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: 0
  current precision for roots: 106
  current precision for roots: 212
 current precision for weights: 106
Linear system for weights solvable: 0
  current precision for roots: 212
  current precision for roots: 424
 current precision for weights: 212
Linear system for weights solvable: 1
  current precision for roots: 424
  current precision for roots: 848
 current precision for weights: 424
Linear system for weights solvable: 1
Sufficient bits for target precision reached
-------------------------------------------------
The nodes are:
| (-6.5353092901602163222 - 7.5168318877665795021e-911j)  +/-  (2.03e-247, 2.03e-247j)
| (6.5353092901602163222 + 1.4186522534176017147e-914j)  +/-  (2.03e-247, 2.03e-247j)
| (-3.2991710734043758017 + 3.7062500997761454721e-914j)  +/-  (1.34e-246, 1.34e-246j)
| (7.2320283910255740448 - 7.2234835948332867971e-917j)  +/-  (2.71e-248, 2.71e-248j)
| (5.4338461138927016502 + 1.4684195609132261548e-914j)  +/-  (1.55e-246, 1.55e-246j)
| (-7.2320283910255740448 + 9.41363060482681691e-917j)  +/-  (3.05e-248, 3.05e-248j)
| (10.247605879939416093 + 2.0095630058929531525e-922j)  +/-  (1.48e-250, 1.48e-250j)
| (-1.4473244073922491632 - 2.2580059664036876715e-922j)  +/-  (1e-249, 1e-249j)
| (-5.9545531108138224089 - 2.9263731849542345161e-917j)  +/-  (7.19e-247, 7.19e-247j)
| (-2.3257324861738577455 - 6.8359237217034362589e-922j)  +/-  (8.99e-248, 8.99e-248j)
| (-4.0724246125006589712 - 2.2705647226841303674e-922j)  +/-  (2.73e-246, 2.73e-246j)
| (-10.247605879939416093 - 1.1882583137762602617e-931j)  +/-  (1.71e-250, 1.71e-250j)
| (5.9545531108138224089 + 9.2922987183840876982e-926j)  +/-  (7.13e-247, 7.13e-247j)
| (2.3257324861738577455 - 2.1170189390078941234e-927j)  +/-  (8.12e-248, 8.12e-248j)
| (2.6523562970146739435 - 1.3008098054883815732e-926j)  +/-  (2.88e-247, 2.88e-247j)
| (-5.4338461138927016502 + 4.2162898499009229221e-929j)  +/-  (1.5e-246, 1.5e-246j)
| (-2.6523562970146739435 - 5.5989503830228715382e-941j)  +/-  (2.95e-247, 2.95e-247j)
| (-1.7199925751864889324 - 3.6914676462448704703e-950j)  +/-  (5.39e-249, 5.39e-249j)
| (-2.0031967466865247167 - 8.6137015105530586681e-949j)  +/-  (1.9e-248, 1.9e-248j)
| (-4.9523144512824200476 + 5.8360634077327831139e-960j)  +/-  (2.3e-246, 2.3e-246j)
| (3.6699503734044525347 - 1.2367426591380453053e-969j)  +/-  (1.92e-246, 1.92e-246j)
| (1.4473244073922491632 - 4.4537907230772910293e-986j)  +/-  (9.26e-250, 9.26e-250j)
| (4.9523144512824200476 + 3.4827411504869115542e-981j)  +/-  (2.56e-246, 2.56e-246j)
| (-4.4999907073093915537 + 2.7176405050439120038e-987j)  +/-  (2.7e-246, 2.7e-246j)
| (-1.1361155852109206663 - 4.6114969631030148053e-999j)  +/-  (1.1e-250, 1.1e-250j)
| (0.56506958325557574853 + 8.7721118294241233123e-1001j)  +/-  (1.26e-252, 1.26e-252j)
| (1.1361155852109206663 + 1.637566606390762058e-999j)  +/-  (9.97e-251, 9.97e-251j)
| (1.7199925751864889324 + 7.5855259884148767573e-996j)  +/-  (5.26e-249, 5.26e-249j)
| (-3.6699503734044525347 - 1.0500886320638447798e-994j)  +/-  (1.82e-246, 1.82e-246j)
| (-0.822493629895198066 + 3.242045802451454827e-1006j)  +/-  (1.1e-251, 1.1e-251j)
| (3.2991710734043758017 - 8.7533142330671657752e-1000j)  +/-  (1.25e-246, 1.25e-246j)
| (0.822493629895198066 - 3.2049787172201172944e-1015j)  +/-  (1.09e-251, 1.09e-251j)
| (2.0031967466865247167 + 9.8551348082908705236e-1011j)  +/-  (1.94e-248, 1.94e-248j)
| (4.0724246125006589712 + 8.7028413105176902524e-1009j)  +/-  (2.41e-246, 2.41e-246j)
| (-1.2823347406451529382e-1028 + 2.9509314750760298692e-1028j)  +/-  (1.32e-1026, 1.32e-1026j)
| (-0.56506958325557574853 + 1.8620350286531072181e-1020j)  +/-  (1.16e-252, 1.16e-252j)
| (4.4999907073093915537 + 1.7101238364199988452e-1013j)  +/-  (2.56e-246, 2.56e-246j)
| (0.31197016656801165987 + 2.5765848817760016903e-1026j)  +/-  (1.02e-253, 1.02e-253j)
| (2.9671669279056032485 + 8.8135042410277909188e-1024j)  +/-  (6.9e-247, 6.9e-247j)
| (-2.9671669279056032485 + 7.2964579762207864371e-1040j)  +/-  (7.05e-247, 7.05e-247j)
| (-0.31197016656801165987 + 7.0250687660097462435e-1048j)  +/-  (1.02e-253, 1.02e-253j)
-------------------------------------------------
The weights are:
| (9.9414694681833692319e-20 - 1.6092439406909703618e-930j)  +/-  (1.02e-98, 1.33e-220j)
| (9.9414694681833692319e-20 - 1.8085673933065339106e-929j)  +/-  (4.63e-99, 6.05e-221j)
| (3.7163325180161425298e-06 + 7.8701980103531081052e-919j)  +/-  (3.32e-88, 4.33e-210j)
| (8.7249855283211443455e-24 + 8.9041279195467282081e-932j)  +/-  (5.83e-101, 7.61e-223j)
| (4.2278516466792169135e-14 - 4.6610916971732991216e-926j)  +/-  (1.38e-96, 1.8e-218j)
| (8.7249855283211443455e-24 - 2.8932846983522898941e-931j)  +/-  (7.2e-102, 9.4e-224j)
| (2.9350125387100009123e-38 - 2.5619622328350612398e-939j)  +/-  (3.94e-108, 5.14e-230j)
| (0.020337975192543666895 + 1.1802554947139660793e-916j)  +/-  (7.04e-79, 9.19e-201j)
| (1.2296696748945295241e-16 - 3.2788859705995730244e-927j)  +/-  (8.63e-99, 1.13e-220j)
| (0.00083430121031282521109 - 1.2368951327630597353e-917j)  +/-  (2.86e-86, 3.73e-208j)
| (1.4703220118752458905e-08 - 2.0625201869023669312e-921j)  +/-  (7.77e-94, 1.01e-215j)
| (2.9350125387100009123e-38 + 5.235553380697076561e-939j)  +/-  (1.81e-109, 2.36e-231j)
| (1.2296696748945295241e-16 + 1.1713407238243323765e-927j)  +/-  (1.18e-99, 1.54e-221j)
| (0.00083430121031282521109 - 2.1832861434384575596e-918j)  +/-  (1.87e-89, 2.44e-211j)
| (0.00015871415567607567992 + 5.6181271929996334176e-919j)  +/-  (4.58e-91, 5.98e-213j)
| (4.2278516466792169135e-14 + 1.5454799124008885222e-925j)  +/-  (1.79e-98, 2.34e-220j)
| (0.00015871415567607567992 + 5.0484420966120545735e-918j)  +/-  (3.88e-90, 5.07e-212j)
| (0.0077256099077887020058 - 7.2966390425139906478e-917j)  +/-  (1.89e-86, 2.46e-208j)
| (0.0031361220700960534311 + 3.3064173440893660225e-917j)  +/-  (1.16e-87, 1.51e-209j)
| (5.8664114905320733933e-12 - 4.5498140188373994413e-924j)  +/-  (4.4e-98, 5.74e-220j)
| (3.0995285353899686326e-07 - 2.4990979375151951228e-921j)  +/-  (5.32e-98, 6.94e-220j)
| (0.020337975192543666895 + 4.6566802227084070772e-917j)  +/-  (7.55e-90, 9.85e-212j)
| (5.8664114905320733933e-12 + 1.0119547950791772107e-924j)  +/-  (4.57e-101, 5.97e-223j)
| (3.9813773675999909214e-10 + 1.0305079529517911807e-922j)  +/-  (1.39e-97, 1.81e-219j)
| (0.049927722664659347159 - 1.7814925230926055416e-916j)  +/-  (1.3e-88, 1.7e-210j)
| (0.094398097434344090804 - 3.1266983535061286662e-916j)  +/-  (1.13e-88, 1.48e-210j)
| (0.049927722664659347159 - 8.7633739000502926595e-917j)  +/-  (3.23e-89, 4.21e-211j)
| (0.0077256099077887020058 - 2.3272598668325995811e-917j)  +/-  (7e-92, 9.13e-214j)
| (3.0995285353899686326e-07 + 4.5085405706383838772e-920j)  +/-  (8.9e-96, 1.16e-217j)
| (0.084325330553981677453 + 3.0915362265282213073e-916j)  +/-  (2.02e-90, 2.64e-212j)
| (3.7163325180161425298e-06 + 2.158472239934787423e-920j)  +/-  (1.63e-97, 2.13e-219j)
| (0.084325330553981677453 + 1.8691189476406318702e-916j)  +/-  (1.23e-91, 1.6e-213j)
| (0.0031361220700960534311 + 8.2146015847330258118e-918j)  +/-  (1.22e-93, 1.59e-215j)
| (1.4703220118752458905e-08 + 2.2789387042343643955e-922j)  +/-  (5.9e-100, 7.7e-222j)
| (0.18202720898936017287 - 3.4742776063065932048e-916j)  +/-  (6.81e-93, 8.66e-215j)
| (0.094398097434344090804 - 4.4006892738393151739e-916j)  +/-  (3.56e-93, 4.54e-215j)
| (3.9813773675999909214e-10 - 1.7007364825197019813e-923j)  +/-  (4.03e-101, 5.26e-223j)
| (0.14811167997947719828 + 3.4941941935258651863e-916j)  +/-  (1.94e-93, 2.46e-215j)
| (2.6800943802052920538e-05 - 1.2970709414061071037e-919j)  +/-  (3.56e-97, 4.65e-219j)
| (2.6800943802052920538e-05 - 2.3804672858584947879e-918j)  +/-  (1.74e-97, 2.36e-219j)
| (0.14811167997947719828 + 4.2143515849374210048e-916j)  +/-  (1.26e-93, 1.53e-215j)
