126845

Appears in sequences

• a(n) = Sum_{k=0..floor(n/4)} C(n-2*k,2*k)*2^k.at n=22A098575
• Expansion of (1-x-2*x^2)/(1-2*x-3*x^2-4*x^3+4*x^4).at n=11A108480
• a(n) = ((n+2)/2)*Sum_{k=0..n/2} (Sum_{i=0..n-2*k} (binomial(k+1,n-2*k-i)*binomial(k+i,k))/(k+1)*C(k)), where C(k) is Catalan numbers.at n=14A270724