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, 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

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