24040451

Appears in sequences

• Number of labeled partitions of (n,n) into pairs (i,j).at n=7A108459
• Number of partitions of the set {1,2,...,n} having no blocks that contain only odd entries.at n=14A124421
• Number of partitions of the set {1,2,...,n} having no blocks that contain only even entries.at n=14A124423