7635498336
domain: N
Appears in sequences
- Number of ways to color vertices of a 9-gon using <= n colors, allowing only rotations.at n=16A054623
- For n >= 3, draw a regular n-sided polygon and its n(n-3)/2 diagonals, so there are n(n-1)/2 lines; a(n) is the number of ways to choose a subset of these lines (subsets differing by a rotation are regarded as identical). a(1)=1, a(2)=2 by convention.at n=8A192332