45752

Appears in sequences

• Number of ways of placing n nonattacking queens on n X n board (symmetric solutions count only once).at n=13A002562
• Duplicate of A002562.at n=5A007630
• a(n) = floor(7^7/n).at n=17A057069
• G.f.: (x-1)/(-2*x^2 + 3*x^3 + 2*x - 1).at n=20A102785
• a(n) = floor(n^(3/2))*floor(3+n^(3/2))/2.at n=44A185593
• Number of 4-bead necklaces labeled with numbers -n..n not allowing reversal, with sum zero and avoiding the patterns z z+1 z+2 and z z-1 z-2.at n=31A209116
• L.g.f.: -log(Product_{k>=1} (1 - k*x^k)^k) = Sum_{n>=1} a(n)*x^n/n.at n=20A296601