80940
domain: N
Appears in sequences
- Where A098018(k)=-n.at n=18A098874
- Numbers n such that sigma(n) = 12*phi(n).at n=12A104902
- a(n) =(A001359[n]^2-1)/2.at n=25A117849
- Number of ways to place 2 nonattacking amazons (superqueens) on an n X n board.at n=20A172200
- Number of sequences of length n over {1, -1} with Erdős discrepancy <= 2.at n=29A181740
- Number of regions in a regular drawing of the complete bipartite graph K_{n,n}.at n=26A290131
- Numbers k whose 10's complement mod 10 of their digits is equal to phi(k), the Euler totient function of k.at n=2A300487
- Ulam numbers that are oblong (or promic) numbers.at n=21A379828