Sean H. Breheny wrote: . . > Out of curiosity, though, I tried your test case. > Lo and behold, Win XP's built in compression > utility (a ZIP algorithm) did not recognize the > sequence! I generated a file that contained > 65535 16-bit numbers, in sequence from 0 to > 65534, represented in little endian format in the > file. It compressed from 127 K to 119K. . . Sean, Thank you for you spent your time with the experiment. I suspected about the result, but never tried. There is infinite set of numerical series, so it is not an easy task to select one to certain data. May be heuristic or stochastic technique could help. (Jinx is a stochastic guru with his random pulling bits out from PICs) :-) Mike. -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.