@trinsec @trinsec
x! = x(x-1)(x-2)(x-3)......1
0 is divisible by 0! → 0÷1 = 0
✓10 is divisible by 1! → 10÷1 = 10
✓20 is divisible by 2! → 20÷ 2(2-1) = 20÷(2×1) = 10
✓30 is divisible by 3! → 30÷3(3-1)(3-2) = 30÷(3×2×1) =5
But...

40 is not divisible by 4!
→ 40÷4(4-1)(4-2)(4-3) = 40÷(4×3×2×1) =40/24 = 5/3