Starting with polynomial:
P : 676039/1024*t^12 - 969969/512*t^10 + 2078505/1024*t^8 - 255255/256*t^6 + 225225/1024*t^4 - 9009/512*t^2 + 231/1024
Extension levels are: 12 26
-------------------------------------------------
Trying to find an order 26 Kronrod extension for:
P1 : 676039/1024*t^12 - 969969/512*t^10 + 2078505/1024*t^8 - 255255/256*t^6 + 225225/1024*t^4 - 9009/512*t^2 + 231/1024
Solvable: 1
-------------------------------------------------
Ending with final polynomial:
P : 676039/1024*t^38 - 642844607231824366161323061033355382950511/101315073343332573176365079746587952128*t^36 + 829543499171682542422999573255454974787389095/29527715264395704382400622686144466492416*t^34 - 132375106477459247314193426346905161859152797045/1742135200599346558561636738482523523052544*t^32 + 2506092667036791767635730196007825607106660165275/17856885806143302225256776569445866111288576*t^30 - 3347499095153580224353214782459392575764871255427/17856885806143302225256776569445866111288576*t^28 + 23548474731146766441269128093716244440069897274804041/125873188047504137385835018038023910218473172224*t^26 - 415969931701224874223699011007224452358401432248675/2927283442965212497345000419488928144615655168*t^24 + 17389291516123966673007854833229633351343990516330094725/209704731287141892884801140051347834423976304925184*t^22 - 27227092741053772756058215500874960357995772599007875/730678506226975236532408153489016844682844268032*t^20 + 60764170294673525271464825870893672839898889021682365/4730181908732523899657168572586793257683676050944*t^18 - 630619860092567336790463154910963156753519544151373555/187445051716635898062885052650939395564288417626624*t^16 + 2529586466253917630469685194127490168634534384253806975/3842623560191035910289143579344257609067912561345792*t^14 - 360617497502659928184530801174995579799591217513528775/3842623560191035910289143579344257609067912561345792*t^12 + 36095845110401662979916550617424360818793280723497125/3842623560191035910289143579344257609067912561345792*t^10 - 16809446342686463402500695053532588269272019093919435/26898364921337251372024005055409803263475387929420544*t^8 + 390095884194581155589339164225046134248089919760315/15370494240764143641156574317377030436271650245383168*t^6 - 8377476470137862746779699084238955264768045967075/15370494240764143641156574317377030436271650245383168*t^4 + 71450880390670348833669783285873252985929440925/15370494240764143641156574317377030436271650245383168*t^2 - 101421289318555856047400565502806253584223125/15370494240764143641156574317377030436271650245383168
-------------------------------------------------
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:
| (-0.99381937293232952854 + 2.7345273032190956758e-897j)  +/-  (6.02e-242, 6.02e-242j)
| (-0.99927796258795845889 - 1.1885500183268785354e-926j)  +/-  (3.07e-242, 3.07e-242j)
| (-0.90411725637047485668 - 1.8414905779555920012e-946j)  +/-  (1.15e-242, 1.15e-242j)
| (0.99927796258795845889 - 1.8977815705052267234e-953j)  +/-  (2.75e-242, 2.75e-242j)
| (0.90411725637047485668 - 9.2442123876306331446e-958j)  +/-  (1.11e-242, 1.11e-242j)
| (0.93655622336835242944 + 3.944304038841826208e-956j)  +/-  (2.48e-242, 2.48e-242j)
| (-0.86534135474544746183 + 3.0129554809778968813e-957j)  +/-  (3.94e-243, 3.94e-243j)
| (-0.93655622336835242944 + 3.0760727445243383392e-960j)  +/-  (2.5e-242, 2.5e-242j)
| (-0.98156063424671925069 - 2.8850827335704407708e-967j)  +/-  (5.83e-242, 5.83e-242j)
| (0.99381937293232952854 + 1.4646777200644535349e-977j)  +/-  (6.55e-242, 6.55e-242j)
| (0.86534135474544746183 + 2.3309170871875746829e-980j)  +/-  (4.03e-243, 4.03e-243j)
| (0.98156063424671925069 - 2.8533175697885677028e-980j)  +/-  (5.87e-242, 5.87e-242j)
| (-0.96243116182708369602 - 1.1980200454366166223e-982j)  +/-  (4.45e-242, 4.45e-242j)
| (-0.82049893693481308376 - 1.3934164777453766783e-998j)  +/-  (1.25e-243, 1.25e-243j)
| (0.96243116182708369602 - 7.0157236259564582356e-1003j)  +/-  (4.25e-242, 4.25e-242j)
| (0.76990267419430468704 + 1.7816278479761249994e-1006j)  +/-  (2.87e-244, 2.87e-244j)
| (0.82049893693481308376 + 4.9155679380203038172e-1008j)  +/-  (1.16e-243, 1.16e-243j)
| (-0.36783149899818019375 - 3.9468827510098101275e-1013j)  +/-  (6.55e-250, 6.55e-250j)
| (-0.76990267419430468704 - 9.690387401353465908e-1009j)  +/-  (2.84e-244, 2.84e-244j)
| (-0.12523340851146891547 + 4.8202423195397316686e-1022j)  +/-  (1.16e-253, 1.16e-253j)
| (0.2888017454095650778 + 8.3919389928337910697e-1021j)  +/-  (4.07e-251, 4.07e-251j)
| (0.71390619053787702443 + 1.9077848895846820301e-1014j)  +/-  (5.43e-245, 5.43e-245j)
| (0.20774617492467426914 + 6.1607099408324385033e-1022j)  +/-  (2.05e-252, 2.05e-252j)
| (-0.65290189927931623274 - 3.187052086283032336e-1014j)  +/-  (8.18e-246, 8.18e-246j)
| (-0.71390619053787702443 - 1.6656254751126610018e-1017j)  +/-  (5.18e-245, 5.18e-245j)
| (-0.041842286875995166032 - 1.2617135115801167055e-1026j)  +/-  (4.54e-255, 4.54e-255j)
| (0.65290189927931623274 - 4.0026703280732854839e-1022j)  +/-  (7.85e-246, 7.85e-246j)
| (0.36783149899818019375 - 3.6117655886685542332e-1026j)  +/-  (6.06e-250, 6.06e-250j)
| (-0.20774617492467426914 + 5.9801995429787792574e-1030j)  +/-  (2.18e-252, 2.18e-252j)
| (-0.5873179542866174473 - 4.9772335508378493966e-1025j)  +/-  (9.75e-247, 9.75e-247j)
| (-0.2888017454095650778 - 4.4129373749180155313e-1028j)  +/-  (4.41e-251, 4.41e-251j)
| (0.44428116303155462665 + 9.1890426803743069144e-1026j)  +/-  (8.01e-249, 8.01e-249j)
| (0.51761471334093533372 - 5.9627491966747751217e-1025j)  +/-  (1.03e-247, 1.03e-247j)
| (0.041842286875995166032 + 3.2178252594717751538e-1032j)  +/-  (5.76e-255, 5.76e-255j)
| (-0.51761471334093533372 - 2.6617681864522565684e-1026j)  +/-  (9.96e-248, 9.96e-248j)
| (-0.44428116303155462665 + 3.1726369239356554494e-1028j)  +/-  (8.48e-249, 8.48e-249j)
| (0.12523340851146891547 - 5.6064840530582544115e-1033j)  +/-  (1.16e-253, 1.16e-253j)
| (0.5873179542866174473 + 7.3597289219973823279e-1034j)  +/-  (1.08e-246, 1.08e-246j)
-------------------------------------------------
The weights are:
| (0.0088053431399670167467 + 2.0111621185686524019e-898j)  +/-  (1.75e-75, 8.43e-193j)
| (0.0023529189940660385909 + 1.7118178094091796504e-897j)  +/-  (1.39e-75, 6.69e-193j)
| (0.035648935439600765577 + 5.7055342347344978182e-898j)  +/-  (1.69e-76, 8.17e-194j)
| (0.0023529189940660385909 + 4.6882361539674081837e-900j)  +/-  (7.89e-78, 3.81e-195j)
| (0.035648935439600765577 - 2.6966047710445017327e-899j)  +/-  (1.13e-77, 5.43e-195j)
| (0.029191118609259383274 + 2.3920507748303451808e-899j)  +/-  (1.24e-77, 5.97e-195j)
| (0.041857783237147720809 - 4.3246527205107233701e-898j)  +/-  (3.18e-77, 1.54e-194j)
| (0.029191118609259383274 - 8.0637486341642515375e-898j)  +/-  (4.63e-77, 2.24e-194j)
| (0.015708920863269925966 - 2.7200729349364669188e-897j)  +/-  (7.92e-77, 3.82e-194j)
| (0.0088053431399670167467 - 1.2114098339322825774e-899j)  +/-  (5e-79, 2.41e-196j)
| (0.041857783237147720809 + 2.9885679199546014696e-899j)  +/-  (3.16e-80, 1.52e-197j)
| (0.015708920863269925966 + 1.688012594741462793e-899j)  +/-  (1.78e-79, 8.61e-197j)
| (0.022528412107461025555 + 1.2858652747196573861e-897j)  +/-  (1.06e-78, 5.09e-196j)
| (0.047774920366144862372 + 3.4289486892726318814e-898j)  +/-  (7.09e-81, 3.42e-198j)
| (0.022528412107461025555 - 2.0631820913863303558e-899j)  +/-  (1.19e-79, 5.74e-197j)
| (0.053358631695951672638 + 3.5637814942395021126e-899j)  +/-  (8.14e-83, 3.93e-200j)
| (0.047774920366144862372 - 3.275648372205230656e-899j)  +/-  (5.51e-82, 2.66e-199j)
| (0.077830691472897256076 - 1.2146245428553376234e-898j)  +/-  (1.1e-85, 5.32e-203j)
| (0.053358631695951672638 - 2.8070796094961909493e-898j)  +/-  (2.15e-83, 1.04e-200j)
| (0.083049059966556085255 + 9.044035774660114958e-899j)  +/-  (2.83e-86, 1.37e-203j)
| (0.080136371654148521635 - 6.0156693189249587161e-899j)  +/-  (8.55e-87, 4.12e-204j)
| (0.058568881471674620029 - 3.8580552752262101117e-899j)  +/-  (4.97e-85, 2.4e-202j)
| (0.081879929781907551748 + 6.4913187715121219108e-899j)  +/-  (6.23e-87, 3.01e-204j)
| (0.063368281914962962181 - 2.0109037413968405593e-898j)  +/-  (1.91e-86, 9.2e-204j)
| (0.058568881471674620029 + 2.3537653934070157341e-898j)  +/-  (9.76e-86, 4.71e-203j)
| (0.083635631893559125791 - 8.2810460014858065201e-899j)  +/-  (3.84e-88, 1.85e-205j)
| (0.063368281914962962181 + 4.1631345561939900361e-899j)  +/-  (1.1e-87, 5.3e-205j)
| (0.077830691472897256076 + 5.5839587877049730188e-899j)  +/-  (2.28e-88, 1.1e-205j)
| (0.081879929781907551748 - 9.9224156424303592073e-899j)  +/-  (1.31e-88, 6.34e-206j)
| (0.067722821706872952057 + 1.7439191368907561133e-898j)  +/-  (1.02e-88, 4.9e-206j)
| (0.080136371654148521635 + 1.0944158285128007311e-898j)  +/-  (6.74e-89, 3.25e-206j)
| (0.074979239893821103747 - 5.1887591248118203309e-899j)  +/-  (7.45e-90, 3.59e-207j)
| (0.071602105790731409953 + 4.8237652818753410411e-899j)  +/-  (4.45e-90, 2.15e-207j)
| (0.083635631893559125791 + 7.6119126042108509473e-899j)  +/-  (2.21e-90, 1.07e-207j)
| (0.071602105790731409953 - 1.5310230852137824969e-898j)  +/-  (1.24e-90, 5.97e-208j)
| (0.074979239893821103747 + 1.3578595890041405505e-898j)  +/-  (1.07e-90, 5.13e-208j)
| (0.083049059966556085255 - 7.0197962650651296707e-899j)  +/-  (3.71e-91, 1.84e-208j)
| (0.067722821706872952057 - 4.4835169655781131179e-899j)  +/-  (2.3e-91, 1.03e-208j)
