Hi Fabien and welcome,

you just discovered this phenomenon: http://en.wikipedia.org/wiki/Birthday_problem

and you can be proud having discovered it by yourself!

Alain


On Sun, Jun 15, 2014 at 12:12 AM, Hilaire Fernandes <hilaire.fernandes@gmail.com> wrote:
Hi Fabien,

As other already explained, you just discovered the marvelous Set
collection.

Hilaire

Le 14/06/2014 11:48, Fabian Boucsein a ��crit :
> i am new to Smalltalk and Pharo and today, while
> trying out some examples, i observed an somewhat
> strange behaviour.

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