user
Definitions

In mathematics, **additive primes** are prime numbers for which the sum of their decimal digits are also primes.

Task

Write a program to determine (and show here) all **additive primes** less than **500**.

Optionally, show the **number** of additive primes.

Also see
:   * the OEIS entry:   A046704 additive primes.
    * the prime-numbers entry:   additive primes.
    * the geeks for geeks entry: additive prime number.
    * the prime-numbers fandom: additive primes.
assistant
```
unit sub MAIN ($limit = 500);
say "{+$_} additive primes < $limit:\n{$_».fmt("%" ~ $limit.chars ~ "d").batch(10).join("\n")}",
    with ^$limit .grep: { .is-prime && .comb.sum.is-prime }

```

Output:

```
54 additive primes < 500:
  2   3   5   7  11  23  29  41  43  47
 61  67  83  89 101 113 131 137 139 151
157 173 179 191 193 197 199 223 227 229
241 263 269 281 283 311 313 317 331 337
353 359 373 379 397 401 409 421 443 449
461 463 467 487
```