The `math` module provides integer math utilities. All functions operate on `Int` values unless noted.

```vary
from math import clamp_int, factorial, gcd

let clamped = clamp_int(150, 0, 100)   # 100
let f = factorial(5)                    # 120
let g = gcd(12, 8)                     # 4
```

## Clamping

| **Function** | **Returns** | **Description** |
|----------|-----------|-----------|
| `clamp_int(x, low, high)` | `Int` | Constrain `x` to the range `[low, high]` |
| `clamp_float(x, low, high)` | `Float` | Constrain `x` to the range `[low, high]` |

```vary
from math import clamp_int, clamp_float

let a = clamp_int(-5, 0, 100)      # 0
let b = clamp_int(50, 0, 100)      # 50
let c = clamp_float(3.14, 0.0, 1.0) # 1.0
```

## Sign and predicates

| **Function** | **Returns** | **Description** |
|----------|-----------|-----------|
| `sign(x)` | `Int` | Returns `1` if positive, `-1` if negative, `0` if zero |
| `is_positive(x)` | `Bool` | True if `x > 0` |
| `is_negative(x)` | `Bool` | True if `x < 0` |
| `is_even(x)` | `Bool` | True if `x` is divisible by 2 |
| `is_odd(x)` | `Bool` | True if `x` is not divisible by 2 |

```vary
from math import sign, is_even, is_odd

print(sign(-42))    # -1
print(is_even(10))  # True
print(is_odd(7))    # True
```

## Combinatorics

| **Function** | **Returns** | **Description** |
|----------|-----------|-----------|
| `factorial(n)` | `Int` | Product of 1 to `n`; returns `1` for n=0 |
| `gcd(a, b)` | `Int` | Greatest common divisor of `a` and `b` |
| `lcm(a, b)` | `Int` | Least common multiple of `a` and `b` |

```vary
from math import factorial, gcd, lcm

let f = factorial(6)   # 720
let g = gcd(48, 18)    # 6
let l = lcm(4, 6)      # 12
```