a(n) = 55440 * (3*n)!/((2*n)!*(n+4)!).

Terms

a(0) =2310a(1) =1386a(2) =2310a(3) =5544a(4) =16335a(5) =55055a(6) =204204a(7) =813960a(8) =3432198a(9) =15142050a(10) =69334650a(11) =327523680a(12) =1588667850a(13) =7883530578a(14) =39904290580a(15) =205532444040