Dense clusters of hydrogen or deuterium are suspected to be the predecessor state leading to one form (or all forms) of LENR. The term 'pycno' was coined by Arata for this state, and he was the probably the first to demonstrate that energy gain is possible for this state alone - WITHOUT additional energy input.
A fair question is how many atoms are involved in pycno clusters, typically. One clue may be the no-called "magic" numbers, which are found in nuclei of unusual stability http://en.wikipedia.org/wiki/Magic_number_%28physics%29 http://chemed.chem.wisc.edu/chempaths/GenChem-Textbook/Nuclear-Stability-748 .html If pycno is formed preferentially by the same geometric tendencies, we would expect to see it with 2, 8, 20, 28, 50, 82, 126 protons. As it turns out, many of the transmutation products seen in LENR are also related to these values. More on that later. Jones
