login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A177584 Number of permutations of 2 copies of 1..n avoiding adjacent step pattern up, down, up, down, up, down 0
1, 6, 90, 2350, 99652, 6149364, 520470852, 58016022928, 8228785850728, 1447745572453056 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..10.

CROSSREFS

Sequence in context: A001499 A147630 A221097 * A177558 A177580 A177587

Adjacent sequences:  A177581 A177582 A177583 * A177585 A177586 A177587

KEYWORD

nonn

AUTHOR

R. H. Hardin May 10 2010

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 | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy .

Last modified June 28 16:43 EDT 2017. Contains 288839 sequences.