173376

Appears in sequences

• Triangle T(n,k) of number of minimal 3-covers of a labeled n-set that cover k points of that set uniquely (k=3,..,n).at n=25A057964
• Numbers n such that phi(sigma(n)) = 5*phi(n).at n=26A067708
• a(n) = (Sum_{k=1..n} 1/c(k))*(Product_{j=1..n} c(j)), where c(j) is the j-th composite.at n=5A110957
• Let f_k(n) be the result of applying phi (the Euler totient function A000010) k times to n; a(n) = n*Product_{k=1..oo} f_k(n).at n=42A291782
• a(n) = [x^n] ((Sum_{k=0..n} (k+3)!*x^k)/(Sum_{k=0..n} (k+3)!*(-x)^k))^(1/4).at n=7A303568