1606567

Appears in sequences

• a(n) is the number of binary strings of length n such that no subsequence of length 5 or less contains 4 or more ones.at n=22A125513
• We draw n non-crossing straight line segments inside an n X n square between 2*n grid points on its perimeter in such a way that it is not possible to add more non-crossing line segments between the remaining perimeter grid points. a(n) is the number of distinct possibilities for each n without duplicates by rotation or reflection.at n=7A357757