1334448351

Appears in sequences

• Expansion of (1+27x^2-54x^3)/((1+3x)^2*(1-3x+9 x^2)).at n=16A168075
• a(n) = (n/4)*3^(n/2)*((1+sqrt(3))^2+(-1)^n*(1-sqrt(3))^2).at n=31A187273