Nuclear Physics - Analysis of Same-Atomic-Weight Isotopes
This reasoning suggests why all of the 186 known isotopes that have
atomic weights less than twice the atomic number (except 3He)
are unstable with very short half-lives. It also suggests a reason
why isotopes that have an excessive atomic weight are also all unstable
with very short half-lives, for having too many electrons within the
nucleus pulling the protons around too aggressively. It also appears
to explain why beta- particles (electrons) are generally emitted
during the radioactive decay of such heavier nuclides.
If only the EVEN numbered elements are included, and only isotopes
which have identical numbers of protons and neutrons, a far simpler
Mass Defect graph results (a semi-log format is used here):

The same is true if only the ODD numbered elements are included:

The irregularities that seem to remain will be discussed below,
as they appear to not be irregularities at all.
This presentation was first placed on the Internet in November 2003.
Atomic_Nuclei_1