167319

Appears in sequences

• Wiener index of a benzenoid consisting of a double-step zig-zag chain of n hexagons (n >= 2, s = 2123; see the Gutman et al. reference).at n=29A193395
• a(n) = Sum_{k=0..n} 2^(n-k) * binomial(k+2,2) * binomial(k,n-k)^2.at n=9A391689