619971
domain: N
Appears in sequences
- Number of fixed-point free involutions in a fixed Sylow 2-subgroup of the symmetric group of degree 2n.at n=18A332840
- Number of fixed-point free involutions in a fixed Sylow 2-subgroup of the symmetric group of degree 2n.at n=19A332840
- Number of fixed-point free involutions in a fixed Sylow 2-subgroup of the symmetric group of degree 4n.at n=9A332869