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# core::math::u256_div_mod_n

Returns `a / b (mod n)`, or `None` if `b` is not invertible modulo `n`.

## Signature

```rust theme={null}
pub fn u256_div_mod_n(a: u256, b: u256, n: NonZero) -> Option
```

## Examples

```rust theme={null}
use core::math::u256_inv_mod;

let result = u256_div_mod_n(17, 7, 29);
assert!(result == Some(19));
```