Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
In these examples the nesting trees have been truncated for clarity. Note that in the “random links” nesting tree frequently low order nodes connect directly to high order nodes. This feature is absent from the “random lines” nesting trees, which are statistically self-similar.
