I have a series of messages (limited to only a-z and A-Z) that are encoded such that the sum is taken of every two ASCII values and concatenated. For instance, the message
hello would be decomposed into the pairs
o which would then become
104 + 101,
108 + 108, and
111 which finally is output as
205216111. Each pair is guaranteed to be 3 digits by zero-padding.
Is it possible to trivially decode this final number back into the plaintext? The words are in plain English and each word is capitalized. So far I have attempted to enumerate all possible permutations and identify words from a dictionary list but this has proven to be rather tedious with short messages alone.