Starting with polynomial:
P : 16777216*t^24 - 2315255808*t^22 + 133706022912*t^20 - 4234024058880*t^18 + 80975710126080*t^16 - 971708521512960*t^14 + 7368789621473280*t^12 - 34738579644088320*t^10 + 97702255248998400*t^8 - 151981285942886400*t^6 + 113985964457164800*t^4 - 31087081215590400*t^2 + 1295295050649600
Extension levels are: 24 39
-------------------------------------------------
Trying to find an order 39 Kronrod extension for:
P1 : 16777216*t^24 - 2315255808*t^22 + 133706022912*t^20 - 4234024058880*t^18 + 80975710126080*t^16 - 971708521512960*t^14 + 7368789621473280*t^12 - 34738579644088320*t^10 + 97702255248998400*t^8 - 151981285942886400*t^6 + 113985964457164800*t^4 - 31087081215590400*t^2 + 1295295050649600
Solvable: 1
-------------------------------------------------
Ending with final polynomial:
P : 16777216*t^63 - 18052092025020592833059501613923863873217101824/1510048018601572117403227320260766503*t^61 + 150052464103018705319927209125793737825142563667968/37751200465039302935080683006519162575*t^59 - 30973415820959381507770610503545932360165290068148224/37751200465039302935080683006519162575*t^57 + 342706222036546669660445920121964268344036494228324352/2903938497310715610390821769732243275*t^55 - 95030768448059904189450328286788959396128107737219858432/7550240093007860587016136601303832515*t^53 + 1561476258599874281099515900314907795877839194196767670272/1510048018601572117403227320260766503*t^51 - 506769855657269134538010342028653677337126311201226601660416/7550240093007860587016136601303832515*t^49 + 26447683325166574447038813948648389200355157668408306986057728/7550240093007860587016136601303832515*t^47 - 1123593219697942881416833748799831385835624235414860371046203392/7550240093007860587016136601303832515*t^45 + 7839703069096505967332525154979181891045873931458602606300348416/1510048018601572117403227320260766503*t^43 - 225949226829192389052190940129947025784751577530698546342753411072/1510048018601572117403227320260766503*t^41 + 415438385133175955021912176785181885690408093568174073371838001152/116157539892428624415632870789289731*t^39 - 8252274749063727477313839232994773514652271767401792318258110457856/116157539892428624415632870789289731*t^37 + 136298019301294871106947147800720048354493789202007554049565402225664/116157539892428624415632870789289731*t^35 - 1870041568151377556080402441555287510368143410282332022833025797460480/116157539892428624415632870789289731*t^33 + 21264457186531141228175648889637552446934511847188346535697959954602240/116157539892428624415632870789289731*t^31 - 199657685371840293624962168457089080001759690009105609848577019944803200/116157539892428624415632870789289731*t^29 + 1539894567540341093403290514277272979049768848189161313905833577110126400/116157539892428624415632870789289731*t^27 - 9689586257516091067174321814939044638653510559635706022411871566050261600/116157539892428624415632870789289731*t^25 + 49312077760178575955912502322244524284220038456956860422514052869698210000/116157539892428624415632870789289731*t^23 - 200768709644813579319263081941291028166326553099419786468529715788337167000/116157539892428624415632870789289731*t^21 + 645074382709923879562834997194895985665750609258311833507589271094649870500/116157539892428624415632870789289731*t^19 - 1607920473599923189420793475717325058875269020509849788221316986934377592750/116157539892428624415632870789289731*t^17 + 3042597447560460313719574662837154234883172863301581338188432559986234724125/116157539892428624415632870789289731*t^15 - 8500401519848579700989480420553431870521293647782994574147799652603719081875/232315079784857248831265741578579462*t^13 + 16895079565528129109466456256861370250961344859296956484774680470819669070625/464630159569714497662531483157158924*t^11 - 22707227585737486439951828246930157869875340715622291184219871099166287759375/929260319139428995325062966314317848*t^9 + 19175156711431571808869328229222865573438096009221943318990249039932531640625/1858520638278857990650125932628635696*t^7 - 9068509918891233709451080384914283469316796206820354612914263965363526559375/3717041276557715981300251865257271392*t^5 + 45586592451464082201712359826725333658291524270004786629810068114350734375/172885640770126324711639621639873088*t^3 - 122862490700363325562096551579474485114697396887964807033866758769290921875/14868165106230863925201007461029085568*t
-------------------------------------------------
Computing nodes and weights
  current precision for roots: 53
  current precision for roots: 106
  current precision for roots: 212
 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: 0
  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:
| (7.2068328439587759331 + 5.5253148483547567234e-861j)  +/-  (5.2e-242, 5.2e-242j)
| (-5.2593829276680443674 - 1.2509058184377012553e-858j)  +/-  (3.63e-240, 3.63e-240j)
| (-8.6751700493855922483 - 4.9697245659862467706e-865j)  +/-  (3.02e-244, 3.02e-244j)
| (6.7892563712523505997 + 3.15664644698842831e-860j)  +/-  (1.52e-241, 1.52e-241j)
| (7.6517565256023600789 - 6.3637850906329809758e-864j)  +/-  (1.4e-242, 1.4e-242j)
| (-5.6614681219173555129 + 2.1401345076496450205e-866j)  +/-  (2.57e-240, 2.57e-240j)
| (6.3932110849624193111 + 2.3922013986716197333e-866j)  +/-  (3.86e-241, 3.86e-241j)
| (8.1343729483160051034 + 5.6436124393912056953e-874j)  +/-  (2.56e-243, 2.56e-243j)
| (-3.0125461375655648257 - 2.1454254290690363034e-880j)  +/-  (5.16e-243, 5.16e-243j)
| (3.5200068130345247113 + 3.4328261405546158779e-877j)  +/-  (3.59e-242, 3.59e-242j)
| (-9.3282074239059546509 - 5.1769223244331233423e-889j)  +/-  (1.42e-245, 1.42e-245j)
| (-3.2564627326930264707 + 5.7385215939288048234e-885j)  +/-  (1.4e-242, 1.4e-242j)
| (8.6751700493855922483 - 1.1383660257130665478e-887j)  +/-  (3.22e-244, 3.22e-244j)
| (-2.5238810170114269742 + 2.1375781967404635721e-887j)  +/-  (2.9e-244, 2.9e-244j)
| (-4.625662756423787265 - 9.3634826991108521852e-884j)  +/-  (6.6e-241, 6.6e-241j)
| (-8.1343729483160051034 + 9.9124534453678690711e-886j)  +/-  (2.8e-243, 2.8e-243j)
| (1.5842500109616941485 + 2.1074174841660781131e-889j)  +/-  (2.37e-247, 2.37e-247j)
| (-2.2742125649812346009 - 1.2233367252033860331e-887j)  +/-  (6.43e-245, 6.43e-245j)
| (-1.1267608176112450721 - 1.8701110414262444589e-891j)  +/-  (3.59e-249, 3.59e-249j)
| (5.2593829276680443674 - 7.2294825525181678461e-883j)  +/-  (3.65e-240, 3.65e-240j)
| (6.0159255614257397173 - 9.2114793569941785746e-890j)  +/-  (8.42e-241, 8.42e-241j)
| (9.3282074239059546509 - 1.5777687696751868895e-895j)  +/-  (1.44e-245, 1.44e-245j)
| (-3.7887308154004269113 - 3.149345425156823687e-892j)  +/-  (9.18e-242, 9.18e-242j)
| (-5.4260274759922216835 + 1.43743443649663695e-889j)  +/-  (4.68e-240, 4.68e-240j)
| (-6.3932110849624193111 + 8.7419615786376252311e-891j)  +/-  (3.82e-241, 3.82e-241j)
| (4.0536644024481495039 - 3.2016144048978148085e-889j)  +/-  (2.03e-241, 2.03e-241j)
| (1.8274470089314092975 + 1.1821058986457994569e-902j)  +/-  (2.2e-246, 2.2e-246j)
| (2.7750459336656875866 + 2.7657634280462404346e-897j)  +/-  (1.34e-243, 1.34e-243j)
| (-6.0159255614257397173 - 3.2166066094764558555e-904j)  +/-  (8.49e-241, 8.49e-241j)
| (-2.7750459336656875866 - 7.9777830709599016154e-909j)  +/-  (1.34e-243, 1.34e-243j)
| (2.5238810170114269742 - 1.1935461661566527781e-903j)  +/-  (2.95e-244, 2.95e-244j)
| (1.3431109148422604524 - 2.0176590092412197708e-914j)  +/-  (2.89e-248, 2.89e-248j)
| (1.1267608176112450721 - 3.3148515760034052761e-915j)  +/-  (3.32e-249, 3.32e-249j)
| (3.0125461375655648257 - 4.886038196837392828e-907j)  +/-  (4.71e-243, 4.71e-243j)
| (-7.6517565256023600789 + 4.6582313936490182479e-918j)  +/-  (1.39e-242, 1.39e-242j)
| (-0.90952103450728961371 + 3.4571851754709750193e-925j)  +/-  (3.4e-250, 3.4e-250j)
| (3.2564627326930264707 + 5.3018601050545139604e-915j)  +/-  (1.43e-242, 1.43e-242j)
| (4.3281572810107449932 + 1.0520089302337271907e-922j)  +/-  (4.43e-241, 4.43e-241j)
| (5.4260274759922216835 - 3.2701024696153487549e-931j)  +/-  (4.75e-240, 4.75e-240j)
| (-4.3281572810107449932 + 8.7530649397425070687e-946j)  +/-  (3.95e-241, 3.95e-241j)
| (-6.7892563712523505997 - 1.0919450938831016101e-946j)  +/-  (1.59e-241, 1.59e-241j)
| (-3.5200068130345247113 + 3.7340395149798271953e-947j)  +/-  (3.61e-242, 3.61e-242j)
| (4.9425631142443084177 + 2.3356539214584770204e-943j)  +/-  (1.52e-240, 1.52e-240j)
| (3.7887308154004269113 + 1.9525857894532695409e-955j)  +/-  (9.48e-242, 9.48e-242j)
| (5.6614681219173555129 - 3.2042825332933209298e-964j)  +/-  (2.64e-240, 2.64e-240j)
| (-4.9425631142443084177 - 8.0104442242681809128e-977j)  +/-  (1.34e-240, 1.34e-240j)
| (-4.0536644024481495039 + 1.800772191671635011e-978j)  +/-  (2.15e-241, 2.15e-241j)
| (-7.2068328439587759331 + 1.1473327686129639533e-980j)  +/-  (5.28e-242, 5.28e-242j)
| (0.90952103450728961371 - 4.7232454071343749974e-986j)  +/-  (3.17e-250, 3.17e-250j)
| (2.2742125649812346009 - 4.012723808312845004e-981j)  +/-  (5.98e-245, 5.98e-245j)
| (-2.0490035736616989118 - 5.8000447871283260513e-985j)  +/-  (1.25e-245, 1.25e-245j)
| (-1.8274470089314092975 - 1.9846713865889381158e-985j)  +/-  (2.21e-246, 2.21e-246j)
| (0.22441454747251558515 + 2.9162238055271762364e-992j)  +/-  (7.48e-254, 7.48e-254j)
| (2.0490035736616989118 - 2.6624597707763145844e-984j)  +/-  (1.37e-245, 1.37e-245j)
| (0.674171107037212236 - 4.2281950418207935023e-990j)  +/-  (2.25e-251, 2.25e-251j)
| (-1.5842500109616941485 + 3.6303974490244474432e-986j)  +/-  (2.54e-247, 2.54e-247j)
| (-0.22441454747251558515 - 2.1083206846367974708e-992j)  +/-  (7.48e-254, 7.48e-254j)
| (-1.3431109148422604524 - 8.1228653305439994593e-987j)  +/-  (2.97e-248, 2.97e-248j)
| (2.4390990851199328403e-1014 + 3.9094579014999719692e-1015j)  +/-  (1.56e-1012, 1.56e-1012j)
| (0.44378505930670911629 - 2.3422081913608401288e-991j)  +/-  (1.42e-252, 1.42e-252j)
| (4.625662756423787265 - 1.8458104832580453063e-989j)  +/-  (7.18e-241, 7.18e-241j)
| (-0.674171107037212236 - 5.57751626379620119e-1003j)  +/-  (1.99e-251, 1.99e-251j)
| (-0.44378505930670911629 - 7.4865511130271803145e-1004j)  +/-  (1.25e-252, 1.25e-252j)
-------------------------------------------------
The weights are:
| (6.7346001333814522033e-24 - 1.7964557777669411133e-880j)  +/-  (1.37e-64, 6.92e-184j)
| (1.5788035862874076968e-13 - 5.4972767670688675263e-871j)  +/-  (4.97e-57, 2.52e-176j)
| (6.794372514247844922e-34 - 4.01755048149120952e-886j)  +/-  (1.74e-70, 8.79e-190j)
| (2.1962921358838896548e-21 + 8.1767743959055119669e-879j)  +/-  (2.22e-63, 1.12e-182j)
| (9.725786669532275831e-27 + 2.5575765025893550625e-882j)  +/-  (8.33e-67, 4.22e-186j)
| (2.2635675293303288692e-15 + 1.4074189329474066846e-872j)  +/-  (5.73e-61, 2.9e-180j)
| (3.8686535328678390846e-19 - 3.4960159902404951046e-877j)  +/-  (9.21e-63, 4.66e-182j)
| (5.2472194261034773243e-30 - 2.2907262375754083202e-884j)  +/-  (4.51e-69, 2.28e-188j)
| (1.5202492781479102609e-05 - 4.4737042587471573101e-866j)  +/-  (6.51e-48, 3.29e-167j)
| (6.3126243802851062525e-07 - 7.0825514481648022543e-868j)  +/-  (1.33e-51, 6.73e-171j)
| (6.8964646644691209372e-39 + 3.8950402054138274244e-889j)  +/-  (1.44e-75, 7.27e-195j)
| (3.5667408986129708839e-06 + 1.3740614309190043411e-866j)  +/-  (4.63e-50, 2.34e-169j)
| (6.794372514247844922e-34 + 9.8927565170299316689e-887j)  +/-  (4.86e-72, 2.46e-191j)
| (0.0002463624908860775759 - 3.0807907057510527901e-865j)  +/-  (2.53e-45, 1.28e-164j)
| (8.8814942895009644888e-11 - 1.0353476971700979365e-869j)  +/-  (1.89e-58, 9.56e-178j)
| (5.2472194261034773243e-30 + 1.0606828741325751204e-883j)  +/-  (3.48e-72, 1.76e-191j)
| (0.01136220418225960136 - 3.1198229653093254575e-864j)  +/-  (3.86e-39, 1.96e-158j)
| (0.00076622465029780081754 + 8.2584072299016065119e-865j)  +/-  (3.19e-44, 1.62e-163j)
| (0.033123387519101784457 - 1.7366621340503037216e-863j)  +/-  (7.23e-33, 3.66e-152j)
| (1.5788035862874076968e-13 - 1.8692830879351874974e-872j)  +/-  (1.33e-62, 6.73e-182j)
| (3.975316939318314225e-17 + 1.2898950778796150834e-875j)  +/-  (1.96e-64, 9.94e-184j)
| (6.8964646644691209372e-39 - 1.090190231090672257e-889j)  +/-  (5.6e-76, 2.84e-195j)
| (8.7704851532998711338e-08 + 9.2097176385800925545e-868j)  +/-  (2.11e-56, 1.07e-175j)
| (9.8581018900278544492e-15 - 3.9681407847015562865e-871j)  +/-  (3.46e-63, 1.75e-182j)
| (3.8686535328678390846e-19 + 3.6625527341221930786e-876j)  +/-  (1.66e-68, 8.41e-188j)
| (1.0968792815842538913e-08 - 2.9693912377174343063e-869j)  +/-  (8.26e-61, 4.18e-180j)
| (0.0046705796541537823091 + 1.6207741340368051043e-864j)  +/-  (1.96e-48, 9.92e-168j)
| (6.229624995347073106e-05 + 3.6838738627079782938e-866j)  +/-  (1.72e-55, 8.7e-175j)
| (3.975316939318314225e-17 - 1.9406485663272796742e-874j)  +/-  (3.02e-67, 1.53e-186j)
| (6.229624995347073106e-05 + 1.1927012205690405017e-865j)  +/-  (1.67e-53, 8.47e-173j)
| (0.0002463624908860775759 - 1.0817165556325210964e-865j)  +/-  (2.09e-54, 1.06e-173j)
| (0.021323523449157644126 + 6.401627338700962523e-864j)  +/-  (1.33e-46, 6.74e-166j)
| (0.033123387519101784457 - 1.1234006734098947518e-863j)  +/-  (3.07e-45, 1.55e-164j)
| (1.5202492781479102609e-05 - 1.2136368758119181259e-866j)  +/-  (4.32e-57, 2.19e-176j)
| (9.725786669532275831e-27 - 1.3677293097708937102e-881j)  +/-  (1.1e-75, 5.54e-195j)
| (0.056459145174430878759 + 2.2523812713083111968e-863j)  +/-  (8.63e-47, 4.37e-166j)
| (3.5667408986129708839e-06 + 3.2272259546148771789e-867j)  +/-  (1.59e-58, 8.07e-178j)
| (1.1783462028882194692e-09 + 4.8815149891775401909e-870j)  +/-  (5.36e-64, 2.71e-183j)
| (9.8581018900278544492e-15 + 6.1574468653493401677e-873j)  +/-  (1.27e-67, 6.44e-187j)
| (1.1783462028882194692e-09 + 5.0380737982471657405e-869j)  +/-  (4.92e-65, 2.49e-184j)
| (2.1962921358838896548e-21 - 6.9453153497928842569e-878j)  +/-  (6.9e-74, 3.49e-193j)
| (6.3126243802851062525e-07 - 3.5806185080767733092e-867j)  +/-  (6.23e-62, 3.15e-181j)
| (4.4795920344389959217e-12 + 8.974245062536177834e-872j)  +/-  (2.22e-67, 1.12e-186j)
| (8.7704851532998711338e-08 + 1.4941726363278498937e-868j)  +/-  (1.46e-63, 7.4e-183j)
| (2.2635675293303288692e-15 - 5.1496248657847252477e-874j)  +/-  (3.12e-69, 1.58e-188j)
| (4.4795920344389959217e-12 + 2.8999880750276504467e-870j)  +/-  (3.61e-68, 1.83e-187j)
| (1.0968792815842538913e-08 - 2.2984052008451932149e-868j)  +/-  (1.07e-65, 5.41e-185j)
| (6.7346001333814522033e-24 + 1.1258884939478905394e-879j)  +/-  (6.63e-77, 3.36e-196j)
| (0.056459145174430878759 + 1.587725277954873332e-863j)  +/-  (1.72e-59, 8.7e-179j)
| (0.00076622465029780081754 + 3.2695825612833074041e-865j)  +/-  (1.23e-62, 6.23e-182j)
| (0.0018234710569882218529 - 1.8686348029741452148e-864j)  +/-  (5.2e-63, 2.63e-182j)
| (0.0046705796541537823091 + 3.3490411158678566135e-864j)  +/-  (4.02e-63, 2.04e-182j)
| (0.11807454374396187474 - 3.5011349607547501489e-863j)  +/-  (6.35e-62, 3.21e-181j)
| (0.0018234710569882218529 - 8.2022497186766154244e-865j)  +/-  (7.42e-63, 3.75e-182j)
| (0.084793427559118872089 - 2.1319543787386555749e-863j)  +/-  (1.38e-61, 6.98e-181j)
| (0.01136220418225960136 - 5.8128093287201478626e-864j)  +/-  (1.43e-63, 7.24e-183j)
| (0.11807454374396187474 - 3.8135198981294838311e-863j)  +/-  (4.87e-63, 2.45e-182j)
| (0.021323523449157644126 + 1.0797614506667631129e-863j)  +/-  (1.41e-63, 7.15e-183j)
| (0.12817595596608371203 + 3.7852277928134734767e-863j)  +/-  (6.54e-63, 3.3e-182j)
| (0.10318735584507488576 + 2.8845023224083008322e-863j)  +/-  (4.66e-63, 2.37e-182j)
| (8.8814942895009644888e-11 - 6.6183852329579009483e-871j)  +/-  (5.86e-71, 2.99e-190j)
| (0.084793427559118872089 - 2.7595096839933596421e-863j)  +/-  (4.92e-64, 2.58e-183j)
| (0.10318735584507488576 + 3.4166565805016268524e-863j)  +/-  (7.49e-64, 3.61e-183j)
