S.O.S. Mathematics CyberBoard

Hi
I need some help in finding or developing a compressing technique, which can compress a 7 number string i.e., 11,10,1,2,10,7,5 down to 6 or 5 lossless, that would be amazing.

I already researched many compression technique; Huffman, Run-Length and LZ78 which all do well on large data sets and I only have a few numbers. If it helps by converting the numbers to binary for better compression then I what to known. I know that a solution could be impossible as we would know about it already but may be someone knows a trick to get rid of one digit, then that helps...

Is there any additional information available, such as possibly being able to use other "7 number strings", or properties of the strings that help to identify them?

Binary information could of course be used in many ways. You may also be able to represent the numbers as a generating function...

Also, if you have lots of computing time available, you can get a lot of information on each string which might be enough to suggest a particular method of compression.