  The double-trace from UV to IR flow subtraction of infinities used earlier
for the UV-convergent calculations of the Witten tadpole diagrams being applied
to the bubble self-energy diagrams gives for them the amazingly simple
expressions in case of the four-dimensional boundary space. For every $N = 1...
4$ in the $O(N)$ symmetric scalar fields model with the conformal
Hubbard-Stratonovich field there are three roots of the "old" conformal
bootstrap spectral equations that obey unitarity bound demand.
