Binomial coefficients C(2*n+6,6).

Terms

a(0) =1a(1) =28a(2) =210a(3) =924a(4) =3003a(5) =8008a(6) =18564a(7) =38760a(8) =74613a(9) =134596a(10) =230230a(11) =376740a(12) =593775a(13) =906192a(14) =1344904a(15) =1947792a(16) =2760681a(17) =3838380a(18) =5245786a(19) =7059052a(20) =9366819a(21) =12271512a(22) =15890700a(23) =20358520a(24) =25827165a(25) =32468436a(26) =40475358a(27) =50063860a(28) =61474519a(29) =74974368