179280

Appears in sequences

• Place n equally-spaced points around a circle and join every pair of points by a chord; this divides the circle into a(n) regions.at n=47A006533
• Theta series of direct sum of 3 copies of E_8 lattice (the Niemeier lattice of type E_8^3).at n=2A008411
• a(n) = 2*a(n-1) - a(n-2) + 2*a(n-3) - a(n-4) + a(n-5), n > 5.at n=21A152718