-4868

Appears in sequences

• a(n) = Sum_{t=0..n} g(t)*g(n-t) where g(t) = A002121(t).at n=40A002122
• Expansion of (1-x-x^2-sqrt(1-2*x-5*x^2+10*x^3+x^4))/(2*x^2).at n=15A174399