Looking for variant approach/sketch

[LarryD]

@GolamMostafa

//--------------------------
uint32_t factorialR(uint8_t n)
{
  if (n == 1)
  {
    return 1;
  }
  return (n * factorialR(n - 1));
}

• Let's remember if (n == 1){} takes some time ~560ns.
  560ns * 12 = 6.72us.

• This is all and good but its bed time.