  The Green functions play a big role in the calculation of the local density
of states of the carbon nanostructures. We investigate their nature for the
variously oriented and disclinated graphene-like surface. Next, we investigate
the case of a small perturbation generated by two heptagonal defects and from
the character of the local density of states in the border sites of these
defects we derive their minimal and maximal distance on the perturbed
cylindrical surface. For this purpose, we transform the given surface into a
chain using the Haydock recursion method. We will suppose only the
nearest-neighbor interactions between the atom orbitals, in other words, the
calculations suppose the short-range potential.
