An Analytic proposition (n.) does not exist, the young Wittgenstein declared.
An Atomic proposition (n.) is where all our logical problems can be traced down to, in how its copula has meaning.
An Atomic proposition (n.) is a priori likely to be fundamental, since understanding general propositions depends on it.
Atomic proposition (n.) turned out not to be independent, as the Tractatus assumed: a man 6 ft tall is therefore not 7 ft.
Gödel's proposition (n.) asserts something about itself without mentioning itself.