954720

Appears in sequences

• Number of 3 X n 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 0 0 and 1 1 1 vertically.at n=13A207896
• a(n) = Sum_{k=1..n} floor(k/2)! * floor((n - k)/2)! binomial((n-floor(k/2)-1), n-k).at n=15A339150