586441134417domain: NAppears in sequences1/4 the number of (n+1) X 5 binary arrays with equal numbers of 2 X 2 subblocks with sums 1 and 3.at n=7A1845991/4 the number of (n+1) X 9 binary arrays with equal numbers of 2 X 2 subblocks with sums 1 and 3.at n=3A184603