143787domain: NAppears in sequencesNumber of n X n arrays of squares of integers with every (n-1)X(n-1) subblock summing to 25.at n=1A159416Number of ways to place 4 non-attacking ferses on an n X n board.at n=6A201245Number of idempotent 3X3 -n..n matrices of rank 1.at n=28A221312