539055domain: NAppears in sequencesa(1) = 12; for n >= 1, a(n+1) = abs((a(n) + R(a(n))) * (a(n) - R(a(n)))), where R(k) is the digit reversal of k.at n=2A109867Square array T(n,k) read by ascending antidiagonals: T(n,k) = (p - 1)/2*(2*(n - 1)*p^(n - 1) - (2*n - 3)*p^(n - 2)), n>=2, where p is the k-th odd prime.at n=24A391520