One half of binomial coefficients binomial(2*n-8,9).

Terms

a(0) =5a(1) =110a(2) =1001a(3) =5720a(4) =24310a(5) =83980a(6) =248710a(7) =653752a(8) =1562275a(9) =3453450a(10) =7153575a(11) =14024400a(12) =26225628a(13) =47071640a(14) =81505820a(15) =136719440a(16) =222945905a(17) =354465254a(18) =550858165a(19) =838553320a(20) =1252716850a(21) =1839537700a(22) =2658968130a(23) =3787984200a(24) =5324436975a(25) =7391571330a(26) =10143295635