67392

Appears in sequences

• Numbers k such that phi(k) and cototient(k) are squares but k is not in A054755.at n=27A054756
• Numbers k such that k = phi(sigma(phi(sigma(phi(sigma(k)))))).at n=18A067884
• Table read by antidiagonals: T(n,k) = count of increasing runs in strings of length n*k formed by concatenating k permutations of [n].at n=23A112858
• Numbers n>9 such that n=Abs[(c+d_1)*(c+d_2)*...*(c+d_k)] where d_1 d_2 ... d_k is the decimal expansion of n and c is an integer constant.at n=42A113756
• Permanent of the n-th principal submatrix of A204437.at n=10A204438
• Numbers D such that D^2 = A^3 + B^4 + C^5 and A^2 + B^3 + C^4 = d^2 for some positive integers A, B, C, d.at n=15A256613
• Numbers n such that n is the sum of two nonzero squares while n^2 is the sum of two positive cubes.at n=39A273554
• The number of positive integer sequences of length n with no duplicate substrings of length greater than 1, every number different from its neighbors, and a minimal sum (= A282166(n)).at n=15A284431
• a(n) is the number of permutations pi on n letters such that pi(i) != i (mod 3) for all i.at n=10A340900
• Number of vertex cuts in the n X n black bishop graph.at n=5A362509
• Iterate the function x <- phi(sigma(x)). The sequence has the smallest member of cycles of length 3.at n=3A373453
• Expansion of 1/((1 - x - x^3)^2 - 4*x^4).at n=15A375278
• Numbers which are the minimum of a cycle in the map x -> phi(sigma(x)).at n=22A376256