40280

Appears in sequences

• a(n) is the concatenation of n and 7n.at n=39A009441
• Numbers k such that k*Sum_{d|k} 1/sigma(d) is an integer.at n=25A069166
• Number of permutations of length n such that at least one absolute difference between consecutive elements has a distinct partner.at n=7A084894
• Bond series for first parallel moment of Kagome lattice.at n=12A120546
• a(n) = 5*a(n-1) + 4*a(n-2) with a(1)=5, a(2)=4.at n=6A189748
• Number of -n..n arrays x(0..3) of 4 elements with zero sum and no two or three adjacent elements summing to zero.at n=19A200431
• Sum of the areas of the squares on the sides of the distinct rectangles that can be made with positive integer sides such that L + W = n, W < L.at n=39A294473