# seq

_Peios / Using Peios / Peiosutils / Output and evaluation_

> Print a sequence of numbers from a start to an end.

`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`](/peios/using-peios/peiosutils/output-and-evaluation/printf.md) for the format syntax — and cannot be combined with `-w`.

## Exit status

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

Related content:

- [printf](/peios/using-peios/peiosutils/output-and-evaluation/printf.md)
- [Output and evaluation](/peios/using-peios/peiosutils/output-and-evaluation/overview.md)