285610domain: NAppears in sequencesNumbers of the form (10^i)*(13^j), with i, j >= 0.at n=19A108761Number of 2 X 2 matrices with all terms in {0,1,...,n} and even determinant.at n=25A210369Number of 2 X 2 matrices having all terms in {1,...,n} and even determinant.at n=25A211064