A202215 Number of permutations avoiding the consecutive pattern 43251.

1, 2, 6, 24, 119, 708, 4914, 38977, 347783, 3447982, 37602245, 447353497, 5765670515, 80026435959, 1190091483826, 18877998176267, 318170909582504, 5677911026433716, 106954187252974515, 2120720309936327198, 44152804913927293967, 963022839743497051427

Offset

1,2

Comments

a(n) is the number of permutations on [n] that avoid the consecutive pattern 43251. It is the same as the number of permutations which avoid 15234, 23415 or 51432.

Links

Ray Chandler, Table of n, a(n) for n = 1..40

A. Baxter, B. Nakamura, and D. Zeilberger. Automatic generation of theorems and proofs on enumerating consecutive Wilf-classes

Crossrefs

Cf. A177523, A202213-A202236.

Sequence in context: A202221 A202222 A202214 * A202218 A202219 A202223

Adjacent sequences: A202212 A202213 A202214 * A202216 A202217 A202218

Keyword

nonn

Author

Ray Chandler, Dec 14 2011

Status

approved