568516domain: NAppears in sequencesa(n) = (29*n)^2.at n=26A133496Number of n X 2 0..1 arrays avoiding the patterns 0 1 0 or 1 0 1 in any row, column, diagonal or antidiagonal.at n=12A206981a(n) is the smallest integer k > n such that sqrt(1/n - 1/k) is a rational number; or 0 if no such k exists.at n=57A379816