54552

Appears in sequences

• 1/4 the number of n X n 0..3 symmetric matrices with every element equal to one, two or three horizontal and vertical neighbors.at n=4A211085
• Expansion of e.g.f. 1/(1 + log(1 + x)/(1 + log(1 + x)^2/(1 + log(1 + x)^3/(1 + ...)))), a continued fraction.at n=7A322470
• Triangle read by rows: T(n,k) is the number of permutations of k elements from [1..n] with longest consecutive chain size less than 3.at n=51A340106