4489216domain: NAppears in sequencesa(n) = 0^n/2 + 2^n*(n^2+n+2)/4.at n=16A087431Number of (n+1) X (n+1) 0..1 arrays with the number of rightwards and downwards edge increases in each 2 X 2 subblock differing from the number in all its horizontal and vertical neighbors.at n=15A205064a(n) = A255473(2^n-1).at n=11A255474