126510

Appears in sequences

• Call two meanders from A005316 equivalent if they differ by a reflection in the Y axis (if n even) or by reflections in the X or Y axes (if n odd). Sequence gives number of inequivalent meanders with n crossings.at n=15A077055
• Call two meanders from A005316 with 2n crossings equivalent if they differ by reflections in the X or Y axes. Sequence gives number of inequivalent meanders.at n=8A078592
• a(1)=1. a(n+1) = sum a(k), where the sum is over all positive integers k, k <= n, where each positive integer <= k and coprime to k is also coprime to n.at n=26A124693