2500875
domain: N
Appears in sequences
- Numbers k such that k*sigma(k)*sigma(sigma(k)) is a square.at n=26A116004
- Number of (n+1)X4 0..2 arrays with every 2 X 2 subblock having the same number of clockwise edge increases as its horizontal neighbors and no 2 X 2 subblock having the same number of counterclockwise edge increases as its vertical neighbors.at n=6A205731
- Number of 8X(n+1) 0..2 arrays with every 2 X 2 subblock having the same number of clockwise edge increases as its horizontal neighbors and no 2 X 2 subblock having the same number of counterclockwise edge increases as its vertical neighbors.at n=2A205743