Almost asymptotically optimal flag encoding of the integers

A simple prefix-free encoding scheme for the positive integers is proposed in which a flag of f zeros is used to mark the end of a codeword, and bit stuffing is used to prevent premature appearance of the flag in the conventional binary coding of the integers. It is shown that this coding scheme is universal in the sense defined by P. Elias (1975) and that for large f its asymptotic efficiency is virtually 1