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GradedLieAlgebras :: basisExtLie

basisExtLie -- a basis in a given degree of the Ext-algebra

Synopsis

Description

This gives a basis in the specified degree of ExtUL(k,k) where k=L.field.

i1 : L=lieAlgebra({a,b},{[a,a,b],[b,b,a]})

o1 = L

o1 : LieAlgebra
i2 : basisExtLie(3,2)

o2 = {ext , ext }
         2     3

o2 : List
i3 : extAlgLie 3

o3 = | 2 0 0 |
     | 0 0 2 |
     | 0 0 0 |

              3        3
o3 : Matrix ZZ  <--- ZZ
i4 : L.cache.extAlgRing

o4 = QQ[ext , ext , ext , ext ]
           0     1     2     3

o4 : PolynomialRing

See also

Ways to use basisExtLie :