No, "s" is correct; there's a very obscurely implied ellipsis ("and so on"); previous node's blockquote is verbatim from site. We're looking at a substitution:
$o =~ s/./chr((ord($&)-13+$f*&e)%26+65)/eg;
See Bruce Schneier's Counterpane site, referenced by author's errata.

In reply to Re^3: The science fiction writer who most personifies Perl is: by ww
in thread The science fiction writer who most personifies Perl is: by apl

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