 
Summary: KTheory 16: 201227, 1999.
c 1999 Kluwer Academic Publishers. Printed in the Netherlands.
201
KTheory for the Integer Heisenberg Groups
HELMER ASLAKSEN, SOO TECK LEE and JUDITH PACKER
Department of Mathematics, National University of Singapore, Singapore 119260,
Republic of Singapore. email: aslaksen@math.nus.edu.sg matleest@math.nus.edu.sg
matjpj@math.nus.edu.sg
(Received: October 1996)
Abstract. We give a closed formula for topological Ktheory of the homogeneous space N/ ,
where is the standard integer lattice in the simply connected Heisenberg Lie group N of dimension
2n + 1, n +. The main tools in our calculations are obtained by computing diagonal forms for
certain incidence matrices that arise naturally in combinatorics.
Mathematics Subject Classifications (1991): Primary 19L64, 55R20; Secondary 05B20, 20F18.
Key words: Kgroups, Heisenberg group, incidence matrices.
1. Introduction
Let n be a natural number and let denote the standard integer lattice of the (2n +
1) dimensional simply connected Heisenberg Lie group N. Both of these groups
together with other discrete subgroups of N occur in a wide variety of situations
in representation theory, geometry and mathematical physics. In this paper we will
