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

 

Logo

Annual Appeal: Please make a donation (tax deductible in USA) to keep the OEIS running. Over 5000 articles have referenced us, often saying "we discovered this result with the help of the OEIS".

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A211365 Array read by antidiagonals: T(m,n) = Sum(1<=i<=m) i * (2m+n-1-i)! 1
1, 2, 10, 6, 36, 186, 24, 168, 1032, 6936, 120, 960, 6840, 53040, 462120, 720, 6480, 52560, 461520, 4499280, 48453840, 5040, 50400, 458640, 4495680, 48449520, 571404960, 7321381200, 40320, 443520, 4475520, 48424320, 571374720, 7321345920 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Index numbers (compare A055089) of permutations like (2,4,6,...,1,3,5...).

LINKS

Tilman Piesk, Table of n, a(n) for n = 1..2016

Tilman Piesk, Arrays of permutations (Wikiversity)

EXAMPLE

T(3,2) = Sum( 1 <= i <= 3 ) [ i * (7-i)! ]

= 1*(7-1)! + 2*(7-2)! + 3*(7-3)!

= 1*720 + 2*120 + 3*24

= 1032

CROSSREFS

Cf. A055089.

Sequence in context: A076374 A142954 A082225 * A213135 A037187 A267500

Adjacent sequences:  A211362 A211363 A211364 * A211366 A211367 A211368

KEYWORD

nonn,tabl

AUTHOR

Tilman Piesk, Jun 22 2012

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 December 6 03:02 EST 2016. Contains 278771 sequences.