And just throw this out there, but PI being expressed as "3.14159..." (or rounded even further to "3.142" in this case) is specific to human-centric base-10 math. If this truly is alien in origin, there's no reason to assume that they'd use base-10 math. (And not just base ten math, but base ten AND base 2, like we do. Unless we assume that the aliens have hands with the same number of fingers, and decided to base their math on that fact, just like humans did, etc.)
For the 3-1-4-2 theory to work out, we must read these marking and assume they're binary representations of those digits/numbers, but if this species uses binary for math, then the ratio for the circumference of a circle to its diameter in pure binary (if I did my math right) would be (in binary) 011.001001000 (approximated in 12 binary "digits" and very rounded), which if split into 3-binary-digit groupings would come out as 011 001 001 000, i.e., 3-1-1-0 and not 3-1-4-2. In PURE BINARY.
Just throwing that out there. Personally, I'm very inclined to think that the "numbers" (if indeed they are numbers, which is quite plausible) are NOT a binary representation of a decimal representation of PI, as that's such a purely human thing to do.
Of course, there's nothing (that I know of) that says that the message ISN'T human in origin...
