186461domain: NAppears in sequencesNumbers k that divide 7^k + 4^k.at n=18A045592a(n) = n^2*(n+1)*(3*n+1)/4.at n=22A213827Number of squares and rectangles in the interior of the square with vertices (n,0), (0,n), (-n,0) and (0,-n) in a square (x,y)-grid.at n=22A330805