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

Author

R. H. Hardin, Mar 18 2009

Keywords

• nonn

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

Crossrefs

Cf. A056986, A158005, A116485.

Formula

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

Proof: see A116485.

Extensions

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