214551

Appears in sequences

• Triangle: a(n,m) = number of permutations of (1,2,...,n) with one or more fixed points in the m first positions.at n=43A061018
• Triangle read by rows: T(n,k) is the number of permutations p of [n] for which k is the smallest among the positive differences p(i+1) - p(i); k=0 for the reversal of the identity permutation (0<=k<=n-1).at n=37A180190
• Number of permutations of [n] having at least one succession. A succession of a permutation p is a position i such that p(i+1)-p(i) = 1.at n=8A180191
• Number of compositions of n into exactly two different parts with distinct multiplicities.at n=22A242900
• Number T(n,k) of permutations p of [n] having at least one index i with |p(i)-i| = k; triangle T(n,k), n>=1, 0<=k<=n-1, read by rows.at n=41A306506
• Total number of occurrences of k in the (signed) displacement sets of all permutations of [n+k] divided by k!; square array A(n,k), n>=0, k>=0, read by antidiagonals.at n=53A324362
• Triangle T(n,k) (n >= 1, 0 <= k <= n-1) read by rows: number of distinct permutations after k steps of the "first transposition" algorithm.at n=37A345462