-15864

Appears in sequences

• a(n+1) = a(n-1) + 2 a(n-2) - a(n-4) ; a(0)=1, a(n)=0 for 0 < n < 5.at n=34A181560
• Expansion of Product_{k>=1} 1/(1 - x^k/(1 + x)).at n=25A307626