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A171737 Number of new extreme inequalities for the flag f-vectors of graded posets of rank n that do not come from those of lower ranks. 0
0, 0, 0, 1, 7, 665 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

COMMENTS

The extremes represent the strongest linear inequalities holding for the flag f-vectors of graded posets of these ranks. The flag f-vector counts all chains having prescribed rank sets.

LINKS

Table of n, a(n) for n=1..6.

Billera, L. J. and G. Hetyei, Linear inequalities for flags in graded partially ordered sets, Journal of Combinatorial Theory, Series A, 89 (2000), 77-104. arXiv:math.CO/9706220.

CROSSREFS

Sequence in context: A101811 A092326 A074282 * A013568 A174853 A228928

Adjacent sequences:  A171734 A171735 A171736 * A171738 A171739 A171740

KEYWORD

nonn,more

AUTHOR

Louis J. Billera (billera(AT)cornell.edu), Oct 06 2010

STATUS

approved

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Last modified September 22 15:16 EDT 2018. Contains 315270 sequences. (Running on oeis4.)