546864domain: NAppears in sequencesNumber of peaks in all hill-free Dyck paths of semilength n (a Dyck path is hill-free if it has no peaks at level 1).at n=12A114515Array of coefficients of powers of x^2 for (S(2*n+1,x)/x)^3, with Chebyshev's S polynomials A049310.at n=40A220665