199620

Appears in sequences

• Number of staircase polygons of area n with 3 (staircase polygon) holes on square lattice (not allowing rotations).at n=7A057416
• Number of proper colorings of the 2n-gon with 2 instances of each of n colors under rotational symmetry.at n=5A284664
• Primitive terms of A388022: numbers k that satisfy sigma(k) AND 3*k = 3*k, but none of whose proper divisors satisfy the same condition.at n=32A388025