696107domain: NPropertiesPrimalityPrimeyesAppears in sequencesNumber of (n+2) X 4 0..2 arrays with every 3 X 3 subblock having three equal elements in a row horizontally, vertically, diagonally or antidiagonally exactly three ways, and new values 0..2 introduced in row major order.at n=12A204278Prime numbersat n=56265