<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def nr_of_antenna(nbl, auto_correlations=False):
 """ Compute the number of antenna for the given number of baselines. Can specify whether auto-correlations should be taken into account """

    t = 1 if auto_correlations is False else -1
    return int(t + math.sqrt(1 + 8*nbl)) // 2