2169600

Appears in sequences

• Number of 7-turn rook's tours on an n X n board summed over all starting positions.at n=4A187194
• E.g.f.: Product_{k>=1} (1 + x^(2*k-1)/(2*k-1)) / (1 - x^(2*k-1)/(2*k-1)).at n=9A326859