15505590domain: NAppears in sequencesa(n) = 2^n - C(n,0) - C(n,1) - ... - C(n,8).at n=24A035041Expansion of g.f. (1+z)^(24)/(1-z).at n=15A171445a(n) = binomial(3*n, n + 1)*hypergeom([1, 1 - 2*n], [2 + n], -1).at n=8A321957