169716

Appears in sequences

• Number of nondecreasing arrangements of n+2 numbers in 0..n with the last equal to n and each after the second equal to the sum of one or two of the preceding three.at n=27A190034
• Irregular array read by rows: A(n,k) = number of first coronas of a fixed rhombus r_{n,k} with characteristics of n-fold rotational symmetry in the Euclidean plane, n>=2, 1<=k<=floor(n/2), as explained below.at n=7A233332
• Expansion of (g/(2 - g^2))^2, where g = 1+x*g^2 is the g.f. of A000108.at n=7A391493