86900

Appears in sequences

• Numbers k such that 255*2^k+1 is prime.at n=45A032504
• Numbers k such that usigma(k) = phi(k)*omega(k), where omega(k) is the number of distinct prime divisors of k.at n=26A063795
• Triangular array read by rows: T(n,k) is the number of set partitions of {1,2,...,n} in which the shortest block has length k (1 <= k <= n).at n=56A178979