  Tunneling data on $\mathrm{La_{1.28}Sr_{1.72}Mn_2O_7}$ crystals confirm
Coulomb interaction effects through the $\sqrt{\mathrm{E}}$ dependence of the
density of states. Importantly, the data and analysis at high energy, E, show a
pileup of states: most of the states removed from near the Fermi level are
found between ~40 and 130 meV, from which we infer the possibility of universal
behavior. The agreement of our tunneling data with recent photoemission results
further confirms our analysis.
