41478

Appears in sequences

• Numbers k such that sigma(sigma(sigma(k))) == 6*sigma(k).at n=33A067065
• Number of 4 X (n+1) 0..1 arrays with every 2 X 2 subblock having the same number of equal edges as its horizontal neighbors and a different number from its vertical neighbors, and new values 0..1 introduced in row major order.at n=8A208086
• Triangle T(n,k) of numbers of distinct shapes under rotation of non-extendable (complete) non-self-adjacent simple paths within a square lattice bounded by rectangles with nodal dimensions n and k, n >= k >= 2.at n=14A213249
• a(n) is the number of permutations of length n that avoid the pattern 321 and the mesh pattern (12, 299) or the same sequence for the mesh patterns (12, 395), (12, 419), (12, 425).at n=11A289596
• G.f. satisfies A(x) = A(x^2)/M(x), where M(x) = Sum_{n>=1} mu(n)*x^n and mu(n) = A008683(n), the Moebius function of n.at n=19A378260