2471008281

Appears in sequences

• a(n) = Sum_{k=0..n} 2^(n-k)*C(2n,n-k).at n=11A128418
• Expansion of -(2*x*sqrt(1-8*x^2)-2*x) / (16*x^3+sqrt(1-8*x^2)*(4*x^2+2*x-1)-8*x^2-2*x+1).at n=22A243019