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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
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
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
KEYWORD
nonn,tabl,more
AUTHOR
Emeric Deutsch, May 29 2008
STATUS
approved