251392

Appears in sequences

• Expansion of (1-x)/(1+2*x+2*x^2+2*x^3).at n=28A078071
• a(n) = 2^(n-4)*(4*n^2 - 16*n + 23).at n=9A217529
• a(n) = 1 + Sum_{k=0..n-5} a(k) * a(n-k-5).at n=35A346074
• Numbers k such that sigma(k) = psi(k) + phi(k) + tau(k).at n=5A388001