Empirical: a(n) = (1/3289135461671169127090225152000000)*n^32 + (1/7119340826128071703658496000000)*n^31 + (821/26525285981219105863630848000000)*n^30 + (38221/8841761993739701954543616000000)*n^29 + (130913/304888344611713860501504000000)*n^28 + (281227/8711095560334681728614400000)*n^27 + (36390667/19055521538232116281344000000)*n^26 + (101853331/1116807123119830990848000000)*n^25 + (33581634599/9381179834206580323123200000)*n^24 + (22857221839/195441246545970423398400000)*n^23 + (9916130831/3089980182544986931200000)*n^22 + (2628332033/35314059229085564928000)*n^21 + (3884904248619179/2651202996623598786969600000)*n^20 + (3100565746678649/126247761743980894617600000)*n^19 + (1530220308699587/4360531244446708531200000)*n^18 + (198878550908215523/46512333274098224332800000)*n^17 + (2752025212416356753/62016444365464299110400000)*n^16 + (743145783468989347/1898462582616254054400000)*n^15 + (23321756887378360532299/7953608989870796360908800000)*n^14 + (273294740133873972113/14567049431997795532800000)*n^13 + (80079643766874632977909/764770095179884265472000000)*n^12 + (6128855514064628460623/11587425684543700992000000)*n^11 + (3633774609243010429510969/1465809349094778175488000000)*n^10 + (1085277989324225756185793/104700667792484155392000000)*n^9 + (3237362577074939537203717/88220007121444982784000000)*n^8 + (68354904897996989730179/630142908010321305600000)*n^7 + (47844163427075855494351/136141986298526208000000)*n^6 + (221074312131188459671339/306319469171683968000000)*n^5 + (16611050476929508361393/5922176403985890048000)*n^4 - (135888529572104181091/211506300142353216000)*n^3 + (2559452604881743321/216821934669740400)*n^2 - (75786966971851/18050444111700)*n + 5