57402

Appears in sequences

• Number of integer partitions of n such that every orderless pair of distinct parts has a different sum.at n=48A325857
• Triangle read by rows: T(n,k) is the number of permutations of the cyclic group Z/nZ whose longest embedded arithmetic progression has length k.at n=38A339942
• E.g.f.: exp(exp(2*(exp(x) - 1)) - 1).at n=6A346417
• a(n) = Sum_{i=1..n} Sum_{j=1..n} Sum_{k=1..n} phi(i*j*k) / phi(j*k).at n=18A372663