login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A193935 4-nonnesting permutations. 3
1, 2, 6, 24, 120, 720, 5034, 40087, 356942, 3500551, 37343168, 428886219, 5257753614, 68306562647, 934747457369, 13404687958473, 200554264435218, 3118638648191005, 50236367074036768, 835860362285064716 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Also the number of 4-noncrossing permutations.

LINKS

Table of n, a(n) for n=1..20.

Sophie Burrill, Sergi Elizalde, Marni Mishna and Lily Yen, A generating tree approach to k-nonnesting partitions and permutations, arXiv preprint arXiv:1108.5615 [math.CO], 2011-2014.

S. Corteel, Crossings and alignments of permutations, Adv. Appl. Math 38 (2007) 149-163.

CROSSREFS

Cf. A193938, A193936, A193937.

Sequence in context: A177547 A324136 A177548 * A177534 A164873 A226438

Adjacent sequences:  A193932 A193933 A193934 * A193936 A193937 A193938

KEYWORD

nonn,more

AUTHOR

Lily Yen, Aug 09 2011

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified September 23 20:42 EDT 2021. Contains 347617 sequences. (Running on oeis4.)