223166

Appears in sequences

• Expansion of 1 / ((1-x-x^2-x^3)*(1-x^2-x^3)).at n=20A103322
• a(n) = 2^n*Product_{k=1..floor((n-1)/2)} (1 + 2*cos(k*Pi/n)^2 + 4*cos(k*Pi/n)^4).at n=11A152103