A202226 Number of permutations avoiding the consecutive pattern 34125.

1, 2, 6, 24, 119, 708, 4914, 38979, 347829, 3448722, 37613451, 447524466, 5768361795, 80070563433, 1190848464594, 18891604332045, 318427172178204, 5682965018856093, 107058447534630429, 2122967250258006555, 44203325864880537180, 964206345760838800371

Offset

1,2

Comments

a(n) is the number of permutations on [n] that avoid the consecutive pattern 34125. It is the same as the number of permutations which avoid 14523, 32541 or 52143.

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: A202219 A202223 A202220 * A202227 A202229 A202224

Adjacent sequences: A202223 A202224 A202225 * A202227 A202228 A202229

Keyword

nonn

Author

Ray Chandler, Dec 15 2011

Status

approved