Raminator, on 08 November 2012 - 12:39 PM, said:

OK.

4! = 24

24 + 1 = 25

sqrt(25) = 5

5! = 120

120 + 1 = 121

sqrt(121) = 11

7! = 5040

5040 + 1 =5041

sqrt(5041) = 71

4,5 5,11 and 7,71 are Brown Numbers

But...

6! = 720

720 + 1 = 721

sqrt(721) = 26.85

6 does not generate a Brown Number.

Your current program will find the only know Brown Numbers that are conecutive. The method I propose will find all known Brown Numbers, and with luck, you may even find a few more.