36738144

Appears in sequences

• Number of partitions of {1..2n} that are invariant under a permutation consisting of n 2-cycles.at n=10A002872
• Number of fixed points of permutation of SetPartitions under {1,2,...,n}->{n,n-1,...,1}. Number of symmetric arrangements of non-attacking rooks on upper half of n X n chessboard.at n=20A080107