FUNCTION :  qr - quadratic residues
                

CALLING SEQUENCE :  qr(p)
                    

PARAMETERS :   p - prime == 1 mod 4

SYNOPSIS :   
      Returns quadratic residues mod p that are < p/2
   

EXAMPLES :   

> with(ramarobinsids):
> qr(13);
                           [1, 3, 4]



DISCUSSION :
  1, 3, 4 are the quadratic residues mod 13 that are < 6

SEE ALSO :  

qnr