A047944 Number of 9-colorings of an n X n grid, up to rotational symmetry.
1, 9, 1665, 96870249, 463255057977921, 179474496923598616041129, 5632099886234793640483695986653185, 14316042242555870306568544190208626253583093449, 2947546144434645792880218215353988087374626027116634833972481
Offset: 0
Keywords
Links
- Andrew Howroyd, Table of n, a(n) for n = 0..25
Formula
a(n) = (m^(n^2) + 2 m^((n^2 + 3 (n mod 2))/4) + m^((n^2 + (n mod 2))/2))/4, with m = 9.
Extensions
Terms a(8) and beyond from Andrew Howroyd, Apr 14 2021