69493domain: NPropertiesPrimalityPrimeyesAppears in sequencesPrime quadruples: 2nd term.at n=29A136720Number of (2+2)X(n+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 2 3 4 6 or 7 and every 3X3 column and antidiagonal sum not equal to 2 3 4 6 or 7.at n=9A252409Intersection of A013917 and A071150.at n=33A255017Prime numbersat n=6900