a(n) = (n+1)(n+2)^2*(n+3)^2*(n+4)(11n^4 + 110n^3 + 439n^2 + 820n + 600)/86400.

Terms

a(0) =1a(1) =33a(2) =421a(3) =3171a(4) =16954a(5) =71148a(6) =249228a(7) =758934a(8) =2066559a(9) =5135845a(10) =11828817a(11) =25546885a(12) =52216164a(13) =101751664a(14) =190171248a(15) =342572508a(16) =597234429a(17) =1011161361a(18) =1667449861a(19) =2684929863a(20) =4230610846a(21) =6535551660a(22) =9914869900a(23) =14792713650a(24) =21733135515a(25) =31477936581