SECTIONS IN GAP

Abstract

In this paper we describe a share package XMOD (Alp,

Wensley, 1997) of functions for computing with finite, permutation

crossed modules, their morphisms and derivations; cat'<groups, their

morphisms and their sections, written using the CAP (Schonert, /993)

group theory programming language. We also give the

implementation method of sections to the CAP.

/991 A. M. S. c. 13D99, 16A99, 17899, 17D99, 18D35.

Keywords: Crossed modules, derivation, whitehead multiplication,

Cat'<groups.sections.

Keywords

• section,gap

SECTIONS IN GAP

Abstract

In this paper we describe a share package XMOD (Alp, Wensley, 1997) of functions for computing with finite, permutation crossed modules, their morphisms and derivations; cat'morphisms and their sections, written using the CAP (Schonert, /993) group theory programming language. We also give the implementation method of sections to the CAP. /991 A. M. S. c. 13D99, 16A99, 17899, 17D99, 18D35. ,>A starting point for this paper was to consider the possibility of implementing functions for doing calculations with crossed modules, derivations, actor crossed modules, catl-groups, sections, induced crossed modules and induced cat I-groups in GAP (Schonert, I993).

Keywords

• Crossed modules
• derivation
• whitehead multiplication
• Cat'<groups.sections.

References

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