A322308 Number of permutations sigma such that |sigma(i+j)-sigma(i)| >= 5 for 1 <= i <= n - j, 1 <= j <= 4.

1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 128, 6320, 344872

Offset

0,26

Comments

2 | a(n) for n > 1.

Links

Table of n, a(n) for n=0..28.

Example

a(25) = 2: [5,10,15,20,25,4,9,14,19,24,3,8,13,18,23,2,7,12,17,22,1,6,11,16,21] and its reverse.

Crossrefs

Cf. A179958, A279214, A322281.

Sequence in context: A106320 A106318 A202748 * A277757 A010367 A024344

Adjacent sequences: A322305 A322306 A322307 * A322309 A322310 A322311

Keyword

nonn,more

Author

Seiichi Manyama, Dec 03 2018

Status

approved