504455124domain: NAppears in sequencesNumber of (n+1)X4 binary arrays with every 2X2 subblock sum equal to some horizontal or vertical neighbor 2X2 subblock sum.at n=7A185491Number of (n+1)X9 binary arrays with every 2X2 subblock sum equal to some horizontal or vertical neighbor 2X2 subblock sum.at n=2A185496