6220800

Appears in sequences

• Numbers k such that k = phi(sigma(phi(sigma(k)))).at n=32A067883
• Integers of the form phi(n!)/phi(n)!.at n=7A068114
• a(0)=1; a(n) is the smallest positive integer such that lcm(a(n-1), a(n)) = n!.at n=12A129108
• A049614(n)/A131685(n).at n=14A131978
• Denominator of Laguerre(n, 1).at n=12A160622
• a(n) = n! / A055773(n).at n=12A182922
• a(n) = n! / A055773(n).at n=13A182922
• Permanent of the n-th principal submatrix of A204545.at n=14A204546
• Permanent of the n-th principal submatrix of A204547.at n=13A204548
• Cancellation factor in reducing Sum_{k=0...n} n^k/k! to lowest terms.at n=11A214402
• A multiplicative encoding (compressed) for the exponents of 2 obtained when using Shevelev's algorithm for computing A002326.at n=14A292265
• Iterate the function x <- phi(sigma(x)). The sequence lists the smaller member of cycles of length 2.at n=8A373435
• Numbers which are the minimum of a cycle in the map x -> phi(sigma(x)).at n=34A376256
• a(n) = coefficient of the term that is independent of 2^(1/3) and 2^(2/3) in the expansion of (2^(1/3) + 2^(2/3))^n.at n=16A377117