156495domain: NAppears in sequencesTriangle read by rows: T(n,k) is the number of secondary structures of size n having k stacks of even length (n>=0, k>=0).at n=44A202848Array: row n shows the coefficients of the characteristic polynomial of the n-th principal submatrix of A115255 (in square format); by antidiagonals.at n=24A203005