4969152domain: NAppears in sequencesNumber of symmetric, reduced unit interval schemes with n+1 intervals (n>=1).at n=33A005213Construct triangle in which n-th row is obtained by expanding (1 + x + x^2)^n and take the next-to-central column.at n=15A005717E.g.f. satisfies A(x) = 1 - x*log(1 - x*A(x)^3).at n=8A377687