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`seq`

: Print numeric sequences`seq`

prints a sequence of numbers to standard output. Synopses:

seq [option]…lastseq [option]…firstlastseq [option]…firstincrementlast

`seq`

prints the numbers from `first` to `last` by
`increment`. By default, each number is printed on a separate line.
When `increment` is not specified, it defaults to ‘`1`’,
even when `first` is larger than `last`.
`first` also defaults to ‘`1`’. So `seq 1`

prints
‘`1`’, but `seq 0`

and `seq 10 5`

produce no output.
The sequence of numbers ends when the sum of the current number and
`increment` would become greater than `last`,
so `seq 1 10 10`

only produces ‘`1`’.
`increment` must not be ‘`0`’; use the tool `yes`

to get
repeated output of a constant number.
`first`, `increment` and `last` must not be `NaN`

,
but `inf`

is supported.
Floating-point numbers may be specified in either the current or
the C locale. See Floating point.

The program accepts the following options. Also see Common options. Options must precede operands.

- ‘
`-f`’`format` - ‘
`--format=`’`format` -
Print all numbers using

`format`.`format`must contain exactly one of the ‘`printf`’-style floating point conversion specifications ‘`%a`’, ‘`%e`’, ‘`%f`’, ‘`%g`’, ‘`%A`’, ‘`%E`’, ‘`%F`’, ‘`%G`’. The ‘`%`’ may be followed by zero or more flags taken from the set ‘`-+#0 '`’, then an optional width containing one or more digits, then an optional precision consisting of a ‘`.`’ followed by zero or more digits.`format`may also contain any number of ‘`%%`’ conversion specifications. All conversion specifications have the same meaning as with ‘`printf`’.The default format is derived from

`first`,`step`, and`last`. If these all use a fixed point decimal representation, the default format is ‘`%.`’, where`p`f`p`is the minimum precision that can represent the output numbers exactly. Otherwise, the default format is ‘`%g`’. - ‘
`-s`’`string` - ‘
`--separator=`’`string` -
Separate numbers with

`string`; default is a newline. The output always terminates with a newline. - ‘
`-w`’ - ‘
`--equal-width`’ -
Print all numbers with the same width, by padding with leading zeros.

`first`,`step`, and`last`should all use a fixed point decimal representation. (To have other kinds of padding, use`--format`).

You can get finer-grained control over output with `-f`:

$ seq -f '(%9.2E)' -9e5 1.1e6 1.3e6 (-9.00E+05) ( 2.00E+05) ( 1.30E+06)

If you want hexadecimal integer output, you can use `printf`

to perform the conversion:

$ printf '%x\n' $(seq 1048575 1024 1050623) fffff 1003ff 1007ff

For very long lists of numbers, use xargs to avoid system limitations on the length of an argument list:

$ seq 1000000 | xargs printf '%x\n' | tail -n 3 f423e f423f f4240

To generate octal output, use the printf `%o`

format instead
of `%x`

.

On most systems, seq can produce whole-number output for values up to
at least *2^{53}*. Larger integers are approximated. The details
differ depending on your floating-point implementation.
See Floating point. A common
case is that `seq`

works with integers through *2^{64}*,
and larger integers may not be numerically correct:

$ seq 50000000000000000000 2 50000000000000000004 50000000000000000000 50000000000000000000 50000000000000000004

However, note that when limited to non-negative whole numbers,
an increment of less than 200, and no format-specifying option,
seq can print arbitrarily large numbers.
Therefore `seq inf`

can be used to
generate an infinite sequence of numbers.

Be careful when using `seq`

with outlandish values: otherwise
you may see surprising results, as `seq`

uses floating point
internally. For example, on the x86 platform, where the internal
representation uses a 64-bit fraction, the command:

seq 1 0.0000000000000000001 1.0000000000000000009

outputs 1.0000000000000000007 twice and skips 1.0000000000000000008.

An exit status of zero indicates success, and a nonzero value indicates failure.

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