$ uname -s Darwin $ type seq seq is /usr/bin/seq The man page says -- The seq command first appeared in Plan 9 from Bell Labs. A seq command appeared i

$ uname -s Darwin $ type seq seq is /usr/bin/seq The man page says -- The seq command first appeared in Plan 9 from Bell Labs. A seq command appeared in NetBSD 3.0, and ported to FreeBSD 9.0. This command was based on the command of the same name in Plan 9 from Bell Labs and the GNU core utilities. The GNU seq command first appeared in the 1.13 shell utilities release.