Starting with polynomial:
P : 583401555/32768*t^17 - 300540195/4096*t^15 + 1017958725/8192*t^13 - 456326325/4096*t^11 + 929553625/16384*t^9 - 66927861/4096*t^7 + 20369349/8192*t^5 - 692835/4096*t^3 + 109395/32768*t
Extension levels are: 17 18
-------------------------------------------------
Trying to find an order 18 Kronrod extension for:
P1 : 583401555/32768*t^17 - 300540195/4096*t^15 + 1017958725/8192*t^13 - 456326325/4096*t^11 + 929553625/16384*t^9 - 66927861/4096*t^7 + 20369349/8192*t^5 - 692835/4096*t^3 + 109395/32768*t
Solvable: 1
-------------------------------------------------
Ending with final polynomial:
P : 583401555/32768*t^35 - 188721563625/1212416*t^33 + 90700781076675/145793024*t^31 - 332960713536718575/221168017408*t^29 + 5632429461296045413775/2287209052024832*t^27 - 121814343461138093197047/42313367462459392*t^25 + 389020492535471856910380551175/156878840908706393890816*t^23 - 64975872152340701297581328615925/40631619795354956017721344*t^21 + 3170499143530562786086025633001773325/4081864133675586125813434138624*t^19 - 93064713104804478154759113364828992228975/328185958211650800101525918179508224*t^17 + 5207375289011816703294171102311036088525/67567697278869282373843571389898752*t^15 - 147816228048051242414375185891093992675/9652528182695611767691938769985536*t^13 + 401347208550972401956345536343725075/185625541974915610917152668653568*t^11 - 77119235759767187412948006094632825/371251083949831221834305337307136*t^9 + 1536003944961853580182386046557675/120872445937154351294890109820928*t^7 - 25382117862389049403403206871019/57115551376897111051431590354944*t^5 + 1668422886011357950594476828945/228462205507588444205726361419776*t^3 - 743473288404057206638622158245/20790060701190548422721098889199616*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
Sufficient bits for target precision reached
-------------------------------------------------
The nodes are:
| (-0.97465925696743106745 - 5.6682517068921580074e-398j)  +/-  (1.09e-115, 1.09e-115j)
| (-0.99843297060605807652 + 2.9244258555002381171e-398j)  +/-  (4.14e-116, 4.14e-116j)
| (-0.95067552176876776122 - 1.0623122028040343995e-398j)  +/-  (8.16e-116, 8.16e-116j)
| (0.99843297060605807652 - 2.3879152123208836071e-396j)  +/-  (4.4e-116, 4.4e-116j)
| (0.88023915372698590212 - 2.6943851725062621097e-402j)  +/-  (2.27e-116, 2.27e-116j)
| (0.91909613680389167324 + 2.0068671777523452225e-409j)  +/-  (5.06e-116, 5.06e-116j)
| (0.99057547531441733568 - 3.0990039099763586304e-424j)  +/-  (9.9e-116, 9.9e-116j)
| (-0.83427409285013436308 + 2.7850157394050287333e-438j)  +/-  (7.09e-117, 7.09e-117j)
| (-0.089585639425226635463 - 9.0191864929154501722e-446j)  +/-  (1.01e-126, 1.01e-126j)
| (0.95067552176876776122 - 1.0781961085896281357e-434j)  +/-  (7.91e-116, 7.91e-116j)
| (0.83427409285013436308 - 1.3955119909592586478e-446j)  +/-  (7.42e-117, 7.42e-117j)
| (0.97465925696743106745 + 9.719089399990532983e-447j)  +/-  (1.17e-115, 1.17e-115j)
| (-0.91909613680389167324 - 2.9438429280468824698e-453j)  +/-  (4.8e-116, 4.8e-116j)
| (-0.88023915372698590212 + 1.3349902093466950876e-455j)  +/-  (2.02e-116, 2.02e-116j)
| (-0.78151400389680140693 + 1.2497135187830773034e-457j)  +/-  (1.91e-117, 1.91e-117j)
| (0.78151400389680140693 + 9.9409087330619399194e-459j)  +/-  (2.01e-117, 2.01e-117j)
| (0.65767115921669076585 - 9.2250833379181076876e-460j)  +/-  (6.8e-119, 6.8e-119j)
| (-0.3512317634538763153 + 9.37832539394160151e-466j)  +/-  (6.74e-123, 6.74e-123j)
| (-0.72247228737240990602 - 5.850360459684226554e-459j)  +/-  (4.29e-118, 4.29e-118j)
| (-0.99057547531441733568 + 6.6185747390874789577e-459j)  +/-  (9.61e-116, 9.61e-116j)
| (0.43368729520979937108 - 4.1637500872355794182e-465j)  +/-  (8.46e-122, 8.46e-122j)
| (0.72247228737240990602 - 4.6577752494480281078e-464j)  +/-  (3.88e-118, 3.88e-118j)
| (0.17848418149584785585 - 4.8100647967520867789e-473j)  +/-  (1.94e-125, 1.94e-125j)
| (-0.65767115921669076585 + 9.0220619782686563855e-468j)  +/-  (6.49e-119, 6.49e-119j)
| (-0.51269053708647696789 + 1.8548388083964544523e-470j)  +/-  (1.12e-120, 1.12e-120j)
| (0.089585639425226635463 + 2.2465148658521196048e-473j)  +/-  (8.27e-127, 8.27e-127j)
| (0.58756921233403525157 - 3.5998709415735530965e-468j)  +/-  (9.8e-120, 9.8e-120j)
| (0.3512317634538763153 + 2.6708836429792146262e-471j)  +/-  (6.12e-123, 6.12e-123j)
| (-0.17848418149584785585 - 4.4596343082560736319e-475j)  +/-  (1.83e-125, 1.83e-125j)
| (-0.58756921233403525157 - 1.2641874274412732561e-469j)  +/-  (9.14e-120, 9.14e-120j)
| (-0.26594650745168201911 + 1.2777340305889068961e-472j)  +/-  (3.17e-124, 3.17e-124j)
| (0.26594650745168201911 - 1.4493871560759545655e-472j)  +/-  (3.1e-124, 3.1e-124j)
| (0.51269053708647696789 - 2.9756268271779509629e-470j)  +/-  (1.08e-120, 1.08e-120j)
| (5.273223419462337721e-482 - 3.9998426138817400498e-482j)  +/-  (2.32e-480, 2.32e-480j)
| (-0.43368729520979937108 + 1.5913032843379154173e-470j)  +/-  (8.5e-122, 8.5e-122j)
-------------------------------------------------
The weights are:
| (0.020022233953295123733 + 3.0078037645813367455e-398j)  +/-  (2.17e-18, 2.21e-72j)
| (0.0042189757937769386559 + 4.5218350664477383285e-398j)  +/-  (6.92e-19, 7.04e-73j)
| (0.027856722457863426944 + 1.3013787326166011865e-398j)  +/-  (1.39e-18, 1.42e-72j)
| (0.0042189757937769386559 + 2.5362374816198107502e-396j)  +/-  (2.53e-20, 2.58e-74j)
| (0.042442630205000891179 - 8.6014388112153624891e-397j)  +/-  (2.26e-20, 2.3e-74j)
| (0.0352497467518800321 + 1.0606495861289288297e-396j)  +/-  (2.13e-20, 2.17e-74j)
| (0.011785837562289086048 - 3.7568822115122255742e-396j)  +/-  (1e-20, 1.02e-74j)
| (0.049436141823959067856 + 5.7811950727108930602e-398j)  +/-  (2.44e-23, 2.48e-77j)
| (0.089361845867788885747 + 1.9439057587518792539e-397j)  +/-  (6.05e-24, 6.16e-78j)
| (0.027856722457863426944 - 1.3799232719576950227e-396j)  +/-  (3.28e-21, 3.34e-75j)
| (0.049436141823959067856 + 7.1865005446477640712e-397j)  +/-  (1.64e-22, 1.67e-76j)
| (0.020022233953295123733 + 2.0109300404785185862e-396j)  +/-  (3.72e-21, 3.79e-75j)
| (0.0352497467518800321 + 3.289711050699782014e-398j)  +/-  (7.84e-24, 7.98e-78j)
| (0.042442630205000891179 - 4.5590983261656017224e-398j)  +/-  (3.66e-24, 3.73e-78j)
| (0.055994044530093517036 - 6.9654661965069252644e-398j)  +/-  (2.58e-25, 2.62e-79j)
| (0.055994044530093517036 - 6.1471204510332970395e-397j)  +/-  (2.9e-25, 2.95e-79j)
| (0.067528016718131089923 - 4.7306685720595877327e-397j)  +/-  (1.12e-26, 1.14e-80j)
| (0.083972571991234775428 - 1.4633358962776711486e-397j)  +/-  (2.73e-28, 2.78e-82j)
| (0.062000915268229960367 + 8.1579494443828323727e-398j)  +/-  (1.09e-26, 1.11e-80j)
| (0.011785837562289086048 - 1.0155760557842717482e-397j)  +/-  (3.27e-25, 3.33e-79j)
| (0.080836678440817871304 + 3.4082464007770411898e-397j)  +/-  (8.35e-29, 8.5e-83j)
| (0.062000915268229960367 + 5.358791468823217844e-397j)  +/-  (1.06e-26, 1.08e-80j)
| (0.088308782297604406647 - 2.55712009864240635e-397j)  +/-  (1.63e-29, 1.66e-83j)
| (0.067528016718131089923 - 9.3669955290178086919e-398j)  +/-  (1.55e-28, 1.58e-82j)
| (0.077056223046202163679 - 1.1873390513028341101e-397j)  +/-  (1.6e-29, 1.63e-83j)
| (0.089361845867788885747 + 2.3335334946409229527e-397j)  +/-  (3.75e-30, 3.81e-84j)
| (0.072589890114190143846 + 4.2109798058735415152e-397j)  +/-  (1.98e-29, 2.02e-83j)
| (0.083972571991234775428 - 3.0896288334252280065e-397j)  +/-  (2.86e-30, 2.91e-84j)
| (0.088308782297604406647 - 1.7715309962853489004e-397j)  +/-  (4.39e-31, 4.47e-85j)
| (0.072589890114190143846 + 1.0597309314027822341e-397j)  +/-  (9.49e-31, 9.64e-85j)
| (0.086490532205651936826 + 1.6123619082656387124e-397j)  +/-  (2.63e-31, 2.68e-85j)
| (0.086490532205651936826 + 2.8077078175309123723e-397j)  +/-  (1.5e-31, 1.53e-85j)
| (0.077056223046202163679 - 3.7760080188679856471e-397j)  +/-  (1.63e-31, 1.66e-85j)
| (0.089696421943981365362 - 2.1307298406896925385e-397j)  +/-  (7.74e-32, 7.96e-86j)
| (0.080836678440817871304 + 1.3217909393217250711e-397j)  +/-  (5.12e-32, 5.05e-86j)
