624999

Appears in sequences

• a(n) = Sum_[k unrelated to n and k<n] a(k) = Sum_[k < n such that GCD(k,n) != 1 and k does not divide n ] a(k); a(1) = a(2) = a(3) = a(4) = 1.at n=43A118657
• a(n) = 8*5^n-1.at n=7A198767