864900

Appears in sequences

• Number of ways to place a non-attacking white and black rook on n X n chessboard.at n=30A035287
• a(1) = 5, a(n) = square of sum of previous terms.at n=3A169652
• Numbers with prime factorization p^2*q^2*r^2*s^2 where p, q, r, and s are distinct primes.at n=14A190377
• Number of n X 4 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 0 and 1 1 1 vertically.at n=18A209220
• Composite numbers whose number of proper divisors has a number of proper divisors which has a prime number of proper divisors.at n=26A223457