323999500domain: NAppears in sequencesNumber of meta-Sylvester classes of 2-multiparking functions of length n.at n=9A243696Triangle T, read by rows, where T(n,k) = Sum_{j=1..n-k-1} [T^j](n-1,k) with T(n+1,n) = 2*n+1 and T(n,n)=0 for n>=0, where T^j denotes the j-th matrix power of T.at n=55A243920