A spherical -design
is a finite set
on a sphere
whose equal-weight average agrees with the uniform average
on
for every polynomial
of degree at most
. Thus
Spherical -designs
give the placement of
points on a sphere for use in numerical integration with equal weights.
Delchev and Yordanov (2026) constructed explicit equal-weight spherical 5-designs on
with at most
points for every odd integer
. For odd
, an equal-weight complex
projective design of strength 3 with
points in complex projective
space of dimension
yields a spherical 7-design with exactly
points.