A202218 Number of permutations avoiding the consecutive pattern 32451.

1, 2, 6, 24, 119, 708, 4914, 38977, 347793, 3448182, 37605545, 447406214, 5766525727, 80040747361, 1190340631290, 18882526564227, 318256944873984, 5679619717431613, 106989639176572571, 2121488012937187849, 44170136425049025574, 963430265253564585315

Offset: 1

Author

Ray Chandler, Dec 15 2011

Keywords

• nonn

Comments

a(n) is the number of permutations on [n] that avoid the consecutive pattern 32451. It is the same as the number of permutations which avoid 15423, 34215 or 51243.

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.