43584

Appears in sequences

• a(n) is the number of labeled rooted ordered binary trees T where the nodes are labeled with distinct positive integers, the root has label n, each parent label equals the sum of its children labels, and T cannot be extended.at n=23A348851
• a(n) = Sum_{k=0..floor(n/3)} Stirling2(k,n - 3*k).at n=35A357940
• Numbers x such that there exist three integers 0<x<=y<=z and t>0 such that sigma(x)^2 = sigma(y)^2 = sigma(z)^2 = x^2 + y^2 + z^2 + t^2.at n=30A385531