Example is slightly faked When testing N 84923 one actully find first b smooth z 436 z 2 mod N 20250 which is 2 3 4 5 3 Another important fact is that we find in this example z 505 less than first 513 is square 505 2 mod N 256 which is 2 8 So whole procedure is somehow useless Maybe slightly better number N could be find to better ilustrate its application of Dixon s method 149 156 82 207