1132672domain: NAppears in sequencesNumber of (n+1)X(5+1) 0..2 arrays with the upper median of every 2X2 subblock differing from its horizontal and vertical neighbors by exactly one.at n=20A237634Number of (n+2)X(2+2) 0..1 arrays with each 3X3 subblock having clockwise perimeter pattern 00000001 00000011 or 00001011.at n=15A260495