Resumen de Free central extensions of groups and modular Lie powers of relation modules

Marianne Johnson, Ralph Stöhr

• The most prominent special case of our main result is that the free centre-by-(nilpotent of class ())-by-abelian groups are torsion-free whenever is divisible by at least two distinct primes. This is in stark contrast to the case where is a prime or , where these relatively free groups contain non-trivial elements of finite order.