966156

Appears in sequences

• Number of pairings on a bracelet; number of chord diagrams that can be turned over and having n chords.at n=9A054499
• Triangle T(n,k) read by rows: number of chord diagrams with k isolated bracelets and a total of n chords.at n=36A371305
• Triangle read by rows: T(n,k) is the number of unsensed combinatorial maps with n edges and k vertices, 1 <= k <= n + 1.at n=45A380616