Goto Chapter: Top 1 2 3 4 5 6 Bib Ind
 [Top of Book]  [Contents]   [Previous Chapter]   [Next Chapter] 

6 Relatively free Algebras
 6.1 Computing Kurosh Algebras
 6.2 A Library of Kurosh Algebras
 6.3 Example of accessing the library of Kurosh algebras

6 Relatively free Algebras

As described in [Eic11], the nilpotent quotient algorithm can also be used to determine certain relatively free algebras; that is, algebras that are free within a variety.

6.1 Computing Kurosh Algebras

6.1-1 KuroshAlgebra
‣ KuroshAlgebra( d, n, F )( function )

determines a nilpotent table for the largest associative algebra on d generators over the field F so that every element a of the algebra satisfies a^n = 0.

6.1-2 ExpandExponentLaw
‣ ExpandExponentLaw( T, n )( function )

suppose that T is the nilpotent table of a Kurosh algebra of exponent n defined over a prime field. This function determines polynomials describing the corresponding Kurosh algebras over all fields with the same characteristic as the prime field.

6.2 A Library of Kurosh Algebras

The package contains a library of Kurosh algebras. This can be accessed as follows.

6.2-1 KuroshAlgebraByLib
‣ KuroshAlgebraByLib( d, n, F )( function )

At present, the library contains the Kurosh algebras for n=2, (d,n) = (2,3), (d,n) = (3,3) and F = ℚ or |F| ∈ {2,3,4}, (d,n) = (4,3) and F = ℚ or |F| ∈ {2,3,4}, (d,n) = (2,4) and F = ℚ or |F| ∈ {2,3,4,9}, (d,n) = (2,5) and F = ℚ or |F| ∈ {2,3,4,5,8,9}.

6.3 Example of accessing the library of Kurosh algebras

gap> KuroshAlgebra(2,2,Rationals);
... some printout ..
rec( bas := [ [ 1, 0, 0, 0 ], [ 0, 1, 1, 0 ], [ 0, 0, 0, 1 ], [ 0, 1, 0, 0 ] ]
    , com := false, dim := 3, fld := Rationals, rnk := 2, 
  tab := [ [ [ 0, 0, 0 ], [ 0, 0, -1 ], [ 0, 0, 0 ] ], 
      [ [ 0, 0, 1 ], [ 0, 0, 0 ], [ 0, 0, 0 ] ] ], wds := [ ,, [ 2, 1 ] ], 
  wgs := [ 1, 1, 2 ] )

 

 [Top of Book]  [Contents]   [Previous Chapter]   [Next Chapter] 
Goto Chapter: Top 1 2 3 4 5 6 Bib Ind

generated by GAPDoc2HTML