The techniques of constructing such sequences have been studied formally in combinatorics under the name "generating function". http://en.wikipedia.org/wiki/Generating_function In this case, the sequence 1, 2, 4, ...,…
The techniques of constructing such sequences have been studied formally in combinatorics under the name "generating function". http://en.wikipedia.org/wiki/Generating_function In this case, the sequence 1, 2, 4, ...,…