CAESAR(6) BSD Reference Manual CAESAR(6)NAME
caesar - decrypt caesar cyphers
SYNOPSIS
caesar [rotation]
DESCRIPTION
The caesar utility attempts to decrypt caesar cyphers using English let-
ter 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 specif-
ic 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.
BSDI BSD/OS November 16, 1993 1