seq

seq prints a sequence of numbers, one per line.

seq [options] last
seq [options] first last
seq [options] first increment last

$ seq 3
1
2
3
$ seq 2 2 10
2
4
6
8
10

The three forms control where the sequence starts and how it steps:

seq last — count from 1 up to last.
seq first last — count from first up to last.
seq first increment last — count from first to last, stepping by increment.

The increment may be negative, to count down, and the numbers may be fractional. seq is most often used to drive a loop a fixed number of times.

Options

Option	Effect
`-s`, `--separator=STRING`	Separate the numbers with `STRING` instead of a newline.
`-t`, `--terminator=STRING`	End the output with `STRING` instead of a newline.
`-w`, `--equal-width`	Pad the numbers with leading zeros so they all have the same width.
`-f`, `--format=FORMAT`	Format each number with a `printf`-style floating-point `FORMAT`.

$ seq -s , 1 5
1,2,3,4,5
$ seq -w 8 10
08
09
10

-f takes a single floating-point conversion — see printf for the format syntax — and cannot be combined with -w.

Code	Meaning
`0`	The sequence was printed.
`1`	An argument was not a valid number, the increment was zero, or no argument was given.