### Atom - `Æ!`

- To Factorial Base

Tags: `arithmetic` , `math` , `number` , `array` , `vectorize` , `base`

##### Arity: monadic

This atom is monadic, which means it takes one argument.

##### Functionality

Convert a number to factorial base.

##### Details

Starting from the right, each place value has a maximum allowed digit of `0, 1, 2, ...`

. The place value of each digit is `0!, 1!, 2!, ...`

. For example, `69 Æ!`

gives `[2, 3, 1, 1, 0]`

. This is evaluated as `2×4! + 3×3! + 1×2! + 1×1! + 0×0! = 48 + 18 + 2 + 1 = 69`

.