82954

Appears in sequences

• 4-dimensional analog of centered polygonal numbers. Also number of regions created by sides and diagonals of a convex n-gon in general position.at n=39A006522
• Number of regions in regular n-gon with all diagonals drawn.at n=38A007678
• Expansion of o.g.f. (1-x^2+x^4)/((1-x)^2*(1-x^2)^4*(1-x^3)^4).at n=23A123991
• Number of regions in a polygon whose boundary consists of n+2 equally spaced points around the arc of a semicircle. See Comments for precise definition.at n=36A333643
• a(n) = A007678(2*n+1).at n=19A341735