6104168domain: NAppears in sequencesHalf the number of nX4 binary arrays with the number of 1-1 adjacencies equal to the number of 0-0 adjacencies.at n=6A183250T(n,k)=Half the number of nXk binary arrays with the number of 1-1 adjacencies equal to the number of 0-0 adjacencies.at n=48A183253