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pureResES -- constructs the Eisenbud--Schreyer pure resolution of a given type

Synopsis

Description

Given a degree sequence $d$, this function returns the pure resolution of type $d$ constructed in by Eisenbud and Schreyer in Section 5 of ``Betti numbers of graded modules and cohomology of vector bundles''. The function operates by resolving the output of pureResES1(d,kk).

i1 : d={0,2,4,5};
 
i2 : FF=pureResES(d,ZZ/32003)

        ZZ          3        ZZ          10        ZZ          15        ZZ          8
o2 = (-----[x ..x ])  <-- (-----[x ..x ])   <-- (-----[x ..x ])   <-- (-----[x ..x ])  <-- 0
      32003  0   2         32003  0   2          32003  0   2          32003  0   2         
                                                                                           4
     0                    1                     2                     3

o2 : ChainComplex
 
i3 : betti FF

            0  1  2 3
o3 = total: 3 10 15 8
         0: 3  .  . .
         1: . 10  . .
         2: .  . 15 8

o3 : BettiTally

See also

Ways to use pureResES :

For the programmer

The object pureResES is a method function.