204684

Appears in sequences

• Length of n-th iterate of the mapping 00->0010, 01->100, 10->011 in A289165.at n=29A289177
• a(n) is the number of permutations of length n that avoid the pattern 321 and the mesh pattern (21, 257) or the same sequence for the mesh patterns (21, 261), (21, 273), (21, 277), (21, 321), (21, 325), (21, 337), (21, 341).at n=12A289602