180251
domain: N
Appears in sequences
- Numbers n such that phi(n + phi(n)) = sigma(n).at n=26A074874
- Central coefficients of triangle A182013.at n=7A182016
- Number k such that k^2 + 1 = p*q*r where p,q,r are distinct primes and the sum p+q+r is a perfect square.at n=32A261529
- Number of sets of exactly n positive integers <= n+7 having a square element sum.at n=29A281970