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!)
A140713 Triangle read by rows: T(n,k) is the number of white corners of rank k in all the permutations of {1,2,...,n} (n>=2, 0<=k<=n-2; for definitions see the Eriksson-Linusson references). 1
1, 5, 1, 26, 9, 2, 154, 70, 26, 6, 1044, 562, 268, 102, 24, 8028, 4860, 2700, 1308, 504, 120, 69264, 45756, 28224, 15828, 7728, 3000, 720 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

2,2

COMMENTS

Sum of row n is A140712(n).

T(n,0) = A001705(n-1).

T(n,n-2) = (n-2)!.

REFERENCES

K. Eriksson and S. Linusson. Combinatorics of Fulton's essential set. Duke Mathematical Journal 85(1):61-76, 1996.

LINKS

Table of n, a(n) for n=2..29.

K. Eriksson and S. Linusson, The size of Fulton's essential set, Electronic J. Combinatorics, Vol. 2, #R6, 1995.

K. Eriksson and S. Linusson, Combinatorics of Fulton's essential set, ResearchGate, 1998.

EXAMPLE

Triangle starts:

1;

5,1;

26,9,2;

154,70,26,6;

1044,562,268,102,24;

CROSSREFS

Cf. A001705, A140711, A140712.

Sequence in context: A264131 A075500 A096645 * A125906 A146414 A146374

Adjacent sequences:  A140710 A140711 A140712 * A140714 A140715 A140716

KEYWORD

nonn,tabl,more

AUTHOR

Emeric Deutsch, May 29 2008

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 April 7 13:36 EDT 2020. Contains 333305 sequences. (Running on oeis4.)