56506domain: NAppears in sequencesNumber of (n+2)X(4+2) 0..1 arrays with each 3X3 subblock having clockwise perimeter pattern 00000001 or 00000101.at n=24A259768Numbers k such that sigma(k) = sigma(k+19), where sigma(k) is the sum of the divisors of k.at n=22A321533Indices of records in A218344.at n=14A354740