261324

Appears in sequences

• Number of primitive (aperiodic) palindromic structures using exactly three different symbols.at n=25A056482
• Number of lower triangles of an n X n 0..7 array with each element differing from all of its horizontal and vertical neighbors by one.at n=5A194997
• Number of lower triangles of a 6 X 6 0..n array with each element differing from all of its horizontal and vertical neighbors by one.at n=6A195002