PosetZeta

The zeta function $\zeta(x,y)$ of a finite poset — $1$ when $x \le y$ and $0$ otherwise — whose inverse in the incidence algebra is MoebiusFunction.

PosetZeta(poset, x, y)$1$ when $x \le y$, else $0$

Typed signatures

Type	Package	Applies
(expression<BooleanLattice> | expression<Chain> | expression<DivisorLattice>, value, value) -> integer	incidence	always

Domain: Incidence algebras

Examples

Basic #

$2\mid 12$

live ↗

In$\mathrm{PosetZeta}(\mathrm{DivisorLattice}(12), 2, 12)$Out$1$

$3\nmid 4$

live ↗

In$\mathrm{PosetZeta}(\mathrm{DivisorLattice}(12), 3, 4)$Out$0$

About

Examples	2

See also: MoebiusFunction, IncidenceAlgebra, PosetInterval