229888

Appears in sequences

• a(n) = Sum_{k=0..n-1} T(n,k) * T(n,2n-k), with T given by A027082.at n=9A027105
• Values of n such that (sigma(sigma(n))-phi(phi(n)))/n is an integer (the corresponding integral ratios are given in A136132).at n=34A136131
• Numbers k such that k and k^2 use only the digits 2, 4, 5, 8 and 9.at n=7A137099
• Decimal representation of the diagonal from the origin to the corner of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 918", based on the 5-celled von Neumann neighborhood.at n=17A290674