891072domain: NAppears in sequencesMonotonic ordering of set S generated by these rules: if x and y are in S and x^2 - y^2 > 0 then x^2 - y^2 is in S, and 1 and 3 are in S.at n=20A192647Number of standard Young tableaux with n cells and 7 as last value in the first row.at n=9A245005