1573344

Appears in sequences

• a(n) = Product_{i=1..n} sigma(i) * Sum_{i=1..n} 1/sigma(i).at n=7A067577
• a(n) = (-1)^n * n! * Sum_{k=0..floor(n/2)} n^(n-k) * Stirling1(n-k,k)/(n-k)!.at n=6A362838