OFFSET
0,4
REFERENCES
T. L. Greenough, Enumeration of interval orders without duplicated holdings, Preprint, circa 1976.
LINKS
T. L. Greenough, Enumeration of interval orders without duplicated holdings, Preprint, circa 1976. [Annotated scanned copy]
T. L. Greenough, Enumeration of interval orders without duplicated holdings, Notices of the AMS, Vol 23-2, February 1976, Issue 168, pages A-314 and A-315. [Mentions this paper]
FORMULA
T(n,k) = qfactorial(n)/qfactorial(k)*(-1)^(k), n>=k, where qfactorial(n) is A005329. - Vladimir Kruchinin, Feb 17 2020
EXAMPLE
Triangle begins:
1;
1, -1;
3, -3, 1;
21, -21, 7, -1;
315, -315, 105, -15, 1;
9765, -9765, 3255, -465, 31, -1;
...
CROSSREFS
KEYWORD
sign,tabl
AUTHOR
N. J. A. Sloane, Jul 09 2015
EXTENSIONS
More terms from Alois P. Heinz, Feb 17 2020
STATUS
approved