This model tests whether a number, specified in the "Number" parameter, is prime or not. If it is, a true value is output to
the Display; otherwise, false is output. The Ramp outputs an increasing sequence of numbers starting from 2. For each
number, the Accumulator generates a sequence of its multiples, up to the value of the "Number" parameter. If the
"Number" parameter can be divided by the accumulated value, then it is not prime. Otherwise, a signal is sent to the
Backtrack actor to roll back the state of the Accumulator, which records the current accumulated value. The same signal
is also sent to the Ramp to trigger the output of the next number.