A263755 Triangle read by rows: T(n,k) (n>=1, k>=0) is the number of permutations of n with bounce statistic k.

1, 1, 1, 2, 2, 1, 1, 6, 6, 4, 4, 2, 1, 1, 24, 24, 18, 18, 14, 8, 6, 4, 2, 1, 1, 120, 120, 96, 96, 84, 66, 46, 30, 22, 16, 10, 6, 4, 2, 1, 1

Offset

1,4

Comments

Row sums give A000142, n >= 1.

Links

Table of n, a(n) for n=1..41.

FindStat - Combinatorial Statistic Finder, The "bounce" of a permutation.

Example

Triangle begins:
1,
1,1,
2,2,1,1,
6,6,4,4,2,1,1,
24,24,18,18,14,8,6,4,2,1,1,
120,120,96,96,84,66,46,30,22,16,10,6,4,2,1,1,
...

Crossrefs

Cf. A000142.

Sequence in context: A124773 A129177 A127452 * A135879 A176224 A174640

Adjacent sequences: A263752 A263753 A263754 * A263756 A263757 A263758

Keyword

nonn,tabf

Author

Christian Stump, Oct 19 2015

Status

approved