Array of integer

Hello,in pg_group, grolist give the list of the members of the group
how can i extract with a select request, not the whole list, but first
the one, the second, etc ...  like :select grolist[i] from pg_group where ...i is varying from 0..N
Thank you for answering
-- 
ERTZ Olivier - ertz@illite.u-strasbg.fr - Tel 03 88 35 85 87
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