7420836

Appears in sequences

• Number of "long curves", i.e., topological types of smooth embeddings of the oriented real line into the oriented plane that coincide with the standard immersion x -> (x,0) in the neighborhood of -infinity and +infinity.at n=9A054993
• Triangular array T(n,k) giving number of alternating link diagrams with n >= 0 crossings, k = 0..[n/2] connected components and two external legs.at n=25A062038