2235330domain: NAppears in sequencesNumber of (n+1)X(n+1) 0..2 arrays with every 2X2 subblock nonsingular.at n=2A183689Number of (n+1)X4 0..2 arrays with every 2X2 subblock nonsingular.at n=2A183692T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with every 2X2 subblock nonsingular.at n=12A183698