210033

Appears in sequences

• a(n) = a(n-1) + 3*a(n-2) -2*a(n-3) - 2*a(n-4), where a(0) = 0, a(1) = 0, a(2) = 3, a(3) = 1.at n=24A295856
• Odd numbers k, not powers of primes, such that sigma(k) == 2 modulo 8 and sigma(sigma(k)) == 6 modulo 8.at n=31A332458
• Number of vertices formed when connecting all 4n points on the perimeter of an n X n square by infinite lines.at n=12A345649