A158423 Number of permutations of 1..n containing the relative rank sequence { 23145 } at any spacing.

1, 26, 459, 7034, 101953, 1454402, 20863742, 304906732, 4578822750, 71092815624, 1146499731400, 19270199314388, 338394827020511, 6218127006568582, 119650035623211443, 2410982527835022898, 50846926185692443237, 1121251553648267523078, 25820703260713964268656, 620088145746453017943268

Offset

5,2

Comments

Same series for 43521 12534 54132 35421 31245 12453 54213 43512 23154 21534 45132 35412 31254 21453 45213.

Links

Martin Fuller, Table of n, a(n) for n = 5..38

Eric Weisstein's World of Mathematics, Permutation Pattern

Formula

Conjecture: a(n) + A116485(n) = n!. - Benedict W. J. Irwin, Mar 15 2016

Proof: see A116485.

Crossrefs

Cf. A056986, A158005, A116485.

Sequence in context: A158432 A021974 A158433 * A158430 A158435 A158424

Adjacent sequences: A158420 A158421 A158422 * A158424 A158425 A158426

Keyword

nonn

Author

R. H. Hardin, Mar 18 2009

Extensions

a(17) onwards from A116485, by Martin Fuller, Aug 26 2023

Status

approved