603020domain: NAppears in sequencesNumber of (n+1) X (1+1) 0..3 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 4 (constant-stress 1 X 1 tilings).at n=16A235282Totient numbers k such that 10*k is a nontotient.at n=24A350320