Mersenne: Factoring Depths

[Dave Mullen]

I'd just like to get a clarification on some files I downloaded from the Entropia FTP.   Re the file of exponents, and how far they have been trial factored.   I extracted a range using the decomp program. Each exponent has a number by the side, but I am unclear to what this number refers.   Is it   a) The bitlength of the K value alone i.e. a bit length of 32 would indicate all K values 1 to (2^32) have been tested ?   or   b) The bitlength of 2 x K x Exp + 1 as computed ?   Just to save me repeating previously done work.   Thanks   Dave