a(n) = 5*(n+1)*binomial(n+2,10).

Terms

a(0) =45a(1) =550a(2) =3630a(3) =17160a(4) =65065a(5) =210210a(6) =600600a(7) =1555840a(8) =3719430a(9) =8314020a(10) =17551820a(11) =35271600a(12) =67897830a(13) =125847260a(14) =225544440a(15) =392251200a(16) =663966875a(17) =1096717050a(18) =1771619850a(19) =2804201400a(20) =4356527175a(21) =6652824750a(22) =9999397200a(23) =14809766400a(24) =21636143100a(25) =31208497320