4.4BSD/usr/share/man/cat6/rot13.0

CAESAR(6)                    BSD Reference Manual                    CAESAR(6)

NNAAMMEE
     ccaaeessaarr - decrypt caesar cyphers

SSYYNNOOPPSSIISS
     ccaaeessaarr [_r_o_t_a_t_i_o_n]

DDEESSCCRRIIPPTTIIOONN
     The Nm caesar utility attempts to decrypt caesar cyphers using English
     letter frequency statistics.  Nm Caesar reads from the standard input and
     writes to the standard output.

     The optional numerical argument Ar rotation may be used to specify a spe-
     cific rotation value.

     The frequency (from most common to least) of English letters is as fol-
     lows:

           ETAONRISHDLFCMUGPYWBVKXJQZ

     Their frequencies as a percentage are as follows:

           E(13), T(10.5), A(8.1), O(7.9), N(7.1), R(6.8), I(6.3), S(6.1),
           H(5.2), D(3.8), L(3.4), F(2.9), C(2.7), M(2.5), U(2.4), G(2),
           P(1.9), Y(1.9), W(1.5), B(1.4), V(.9), K(.4), X(.15), J(.13),
           Q(.11), Z(.07).

     Rotated postings to USENET and some of the databases used by the for-
     tune(6) program are rotated by 13 characters.

4.4BSD                           May 31, 1993                                1