4335711domain: NAppears in sequencesa(0)=1; for n >= 1, a(n) = Sum_{k=0..n} 10^k*N(n,k), where N(n,k) = (1/n)*C(n,k)*C(n,k+1) are the Narayana numbers (A001263).at n=7A082148a(n) = N(7,n), where N(7,x) is the 7th Narayana polynomial.at n=10A090200