253797

Appears in sequences

• Hilltop maps: number of 2Xn binary arrays indicating the locations of corresponding elements not exceeded by any horizontal or antidiagonal neighbor in a random 0..3 2Xn array.at n=8A218811
• Expansion of g/(1 - x^3*g^2), where g = 1+x*g^2 is the g.f. of A000108.at n=12A391031