I'm finding this surprisingly challenging.

Example:

```
library(tidyverse)
diamonds %>% mutate(DummyCategory = LETTERS[1:3])
Error: Problem with `mutate()` input `DummyCategory`.
x Input `DummyCategory` can't be recycled to size 53940.
ℹ Input `DummyCategory` is `LETTERS[1:3]`.
ℹ Input `DummyCategory` must be size 53940 or 1, not 3.

```

Tried base R

```
 my_diamonds <- diamonds
> my_diamonds$DummyCategory <- LETTERS[1:3]
Error: Assigned data `LETTERS[1:3]` must be compatible with existing data.
x Existing data has 53940 rows.
x Assigned data has 3 rows.
ℹ Only vectors of size 1 are recycled.

```

I would like a new column DummyCategory To be the values A, B, C, recycled to however long the dataframe is and it doesn't matter if A,B,C are not divisible by nrow of end up with differing frequencies, I'd just like to recycle till all rows in diamonds have a new DummyCategory. How can I do this?