Man

Command Section
CAESAR(6)                    FreeBSD Games Manual                    CAESAR(6)

NAME
     caesar, rot13 - decrypt caesar ciphers

SYNOPSIS
     caesar [rotation]
     rot13

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

     The optional numerical argument rotation may be used to specify a
     specific rotation value.  If invoked as rot13, a rotation value of 13
     will be used.

     The frequency (from most common to least) of English letters is as
     follows:

           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
     fortune(6) program are rotated by 13 characters.

FreeBSD 11.1-RELEASE-p4        November 16, 1993       FreeBSD 11.1-RELEASE-p4
Command Section