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Posets :: flagfPolynomial

flagfPolynomial -- computes the flag-f polynomial of a ranked poset

Synopsis

Description

Suppose P is a rank r poset. For each strictly increasing sequence (i1, ..., ik) with 0 ≤ij ≤ik, the coefficient of qi1 …qik is the number of flagChains in the ranks i1, …, ik.

The flag-f polynomial of the n chain is (q0 + 1)…(qn-1+1).
i1 : n = 4;
i2 : factor flagfPolynomial chain n

o2 = (q  + 1)(q  + 1)(q  + 1)(q  + 1)
       3       2       1       0

o2 : Expression of class Product

See also

Ways to use flagfPolynomial :