104124

Appears in sequences

• Number of (w,x,y,z) with all terms in {1,...,n} and w <= harmonic mean of {x,y,z}.at n=23A212104
• a(0) = ... = a(4) = 1; a(n) = Sum_{k=0..n-5} binomial(n-5,k) * a(k) * a(n-k-5).at n=18A336010