Empirical: a(n) = (1/4274883284060025564298013753389399649690343788366813724672000000000000)*n^53 + (1/2987339821146069576728171735422361739825537238551232512000000000000)*n^52 + (1/4293754334359535723804132917562085013323902339147366400000000000)*n^51 + (983/9358182523604116321111571743404544259808505098141696000000000000)*n^50 + (919/26601247698291584294704905101514375082546042188595200000000000)*n^49 + (2193739/248278311850721453417245780947467500770429727093555200000000000)*n^48 + (3691013/2016961140760212967799675589902057066220125442539520000000000)*n^47 + (13008397/41223657652103943972122689500042043345264548249600000000000)*n^46 + (445905813989/9646335890592322889476709343009838142791904290406400000000000)*n^45 + (18780299330173/3215445296864107629825569781003279380930634763468800000000000)*n^44 + (10442307489167/16212329227886256957103713181529139735784713093120000000000)*n^43 + (668499471681023/10682542514498696444603221863798270368540314828800000000000)*n^42 + (7870219056400890253/1458167053229072064688339784408463905305752974131200000000000)*n^41 + (273861694002189907/658612038495515837709277228730110164998081740800000000000)*n^40 + (1573702262991812389/54715461659627469594309185156039921399840636928000000000)*n^39 + (3311204480544845033/1846000730756662267014479931040483178132275200000000000)*n^38 + (9154178946016451047/90439746872710061371901512573559723419238400000000000)*n^37 + (32658199362613018320851/6300635698798800942242472042624660731540275200000000000)*n^36 + (7141636537276995681777691/29575925221420253834761721705967525080994938880000000000)*n^35 + (996944606490802545704507/97225263712755601034719663727703895729766400000000000)*n^34 + (73492055660680026329490992437/184849532633876586467260760662297031756218368000000000000)*n^33 + (1736807153877211874198930742823/123233021755917724311507173774864687837478912000000000000)*n^32 + (3583376061273513624689959541741/7836938710744998135939165889830104572153036800000000000)*n^31 + (177464052841242008949428522572687/13061564517908330226565276483050174286921728000000000000)*n^30 + (527677136181050381538830061580310473/1426322845355589660740928191949079032131852697600000000000)*n^29 + (50459285404367689387410758262805823/5464838487952450807436506482563521195907481600000000000)*n^28 + (854729747156206462969232817925303/4046363339495850042528059098566161313300480000000000)*n^27 + (429605392354242941966828061045302251/97008967241759481788813724542547713536819200000000000)*n^26 + (666495784492947163492582785815452578827/7836938710744998135939165889830104572153036800000000000)*n^25 + (42450622440006578972724654189285557017/28394705473713761362098427137065596275916800000000000)*n^24 + (22214227838882515956407944009993603990511/924247663169382932336303803311485158781091840000000000)*n^23 + (3098000159169716206064429771980351145707/8777280751845991760078858530973268364492800000000000)*n^22 + (371391995002403481958058652876650926298830919/78561051369397549248585823281476238496392806400000000000)*n^21 + (2482535555594433445009478291179283884149071/43070751847257428316110648728879516719513600000000000)*n^20 + (110856867993340004971876951487026057789523/173730763753643408333891692351782924582912000000000)*n^19 + (9255071614260555422527966847510911255107761/1447756364613695069449097436264857704857600000000000)*n^18 + (242905258110399278971029297594386453078012136643/4209878086974177939903050467735079179675238400000000000)*n^17 + (1800034702435193979298619077572575860278812510519/3859054913059663111577796262090489248035635200000000000)*n^16 + (24880512378555625947667623998077597599135057623/7421259448191659829957300504020171630837760000000000)*n^15 + (2072215723007383599112484941711317977368870589/97583950666556999736453655542671553331200000000000)*n^14 + (28336889740780092254461964719743628364083285185503/241485426488776232562102635448275426082816000000000000)*n^13 + (469579414878808641318387730560089588715470727961/838491064197139696396189706417623007232000000000000)*n^12 + (95308730395622220165413193737805668794361045211377/41569427582667608007218157915810157087948800000000000)*n^11 + (15298499732022400890579708293951960035784833136357/1887500718230099722549969777160183414784000000000000)*n^10 + (582506603414565939238327344321169532458998163383581/22574508590031992681697638534835793640816640000000000)*n^9 + (157964339061200364578998048322498253958910309969/1959592759551388253619586678371162642432000000000)*n^8 + (28268026362458256637304068608121959155752558393/109359091293702706250235931883867481047040000000)*n^7 + (64016812094557369612777065511323671447287361729/83538194738245122830041336855732103577600000000)*n^6 + (23633230908129818070364487397727423989191446541/13187100740822980103885096746511996350464000000)*n^5 + (16469905449790360428529720067986410092401501/5232976484453563533287736804171427123200000)*n^4 + (366403259490785057806075130022937259/85420730975781792281047984763136000)*n^3 + (2852802490628373640019067479/713726260088401704624480000)*n^2 + (22194662238782354/13601737478654325)*n