# ApCoCoA-1:BB.NDneighbors

From ApCoCoAWiki

## BB.NDneighbors

Compute a list of next-door neighbors.

### Syntax

BB.NDneighbors(OO:LIST):LIST

### Description

Computes the list of next-door neighbors in the border of the order ideal OO. The input is a list OO of terms that specify an order ideal. The output is a list of triples [i,j,k] such that b_i = x_k * b_j.

@param

*OO*A list of terms representing an order ideal.@return A list of next-door neighbors of OO.

#### Example

Use QQ[x,y,z]; BB.NDneighbors([1,x]); [[3, 1, 1], [4, 2, 1]] -------------------------------