10349536

Appears in sequences

• Number of self-inverse permutations on n letters, also known as involutions; number of standard Young tableaux with n cells.at n=15A000085
• Bisection of A000085.at n=7A066224
• Number of permutations in the symmetric group S_n such that the size of their conjugacy class is odd.at n=14A088042
• Number of involutions in the symmetric group S_n with at least one fixed point.at n=15A378100
• Number of permutations of [n] whose compositional square is the identity permutation or its reverse.at n=15A383835