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

Terms

a(0) =1a(1) =10a(2) =95a(3) =920a(4) =9135a(5) =92752a(6) =959595a(7) =10084360a(8) =107375730a(9) =1156073100a(10) =12565671261a(11) =137702922560