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TSpreadIdeals > tSpreadList

tSpreadList -- give the set of all t-spread monomials of a given list

Synopsis

Description

the function tSpreadList(l,t) gives the list of all the t-spread monomials l.
This function calls the method isTSpread(u,t) to check whether the monomial u is t-spread, for all the monomials that belong to the list l.
Let $u=x_{i_1}x_{i_2}\cdots x_{i_d}$ a monomial of $S=K[x_1,\ldots,x_n]$, with $1\le i_1\le i_2\le\dots\le i_d\le n$. The monomial u is called $t$-spread if $i_{j+1}-i_j\ge t$ for all $j\in [d-1]$.

Examples:

i1 : S=QQ[x_1..x_14]

o1 = S

o1 : PolynomialRing
 
i2 : l={x_3*x_7*x_10*x_14, x_1*x_5*x_9*x_13}

o2 = {x x x  x  , x x x x  }
       3 7 10 14   1 5 9 13

o2 : List
 
i3 : tSpreadList(l,4)

o3 = {x x x x  }
       1 5 9 13

o3 : List
 
i4 : tSpreadList(l,5)

o4 = {}

o4 : List

See also

Ways to use tSpreadList :

For the programmer

The object tSpreadList is a method function.