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ResolutionsOfStanleyReisnerRings :: sumBetti

sumBetti -- Computes the sum of Betti numbers.

Synopsis

Description

i1 : S = QQ[a..f];
i2 : m = matrix{{a,b,d,e},{b,c,e,f}}

o2 = | a b d e |
     | b c e f |

             2       4
o2 : Matrix S  <--- S
i3 : M = coker m

o3 = cokernel | a b d e |
              | b c e f |

                            2
o3 : S-module, quotient of S
i4 : sumBetti M

o4 = 12

See also

Ways to use sumBetti :

For the programmer

The object sumBetti is a method function.