651065domain: NAppears in sequencesNumber of paths from (0,0) to (n,0), with vertices (i,k) satisfying 0 <= k <= 3, consisting of segments given by the vectors (1,1), (1,2), (1,-1).at n=23A247323G.f. A(x) satisfies A(x) = ( 1 + x * A(x*A(x))^(1/4) )^4.at n=8A384578