46498

Appears in sequences

• Number of distinct non-extendable sequences X={x(1),x(2),...,x(k)} where x(1)=1, the x(i)'s are distinct elements of {1,...,n} with |x(i)-x(i+1)|=1 or 2, for i=1,2,...,k.at n=17A054668
• Numbers m such that sigma(m+1)+sigma(m-1) = 5*phi(m).at n=22A067242
• Expansion of x^2/(1 - 2*x + 2*x^2 - x^3 - x^4).at n=33A113021
• Numbers k such that (10^k-1)*120/99 + 1 is prime.at n=10A153328
• Numbers n such that if x=phi(n)*tau(n)-sigma(n)-n then n=phi(x)*tau(x)-sigma(x)-x.at n=5A238231