Question 1

What rule does Rule 30 run?

Accepted Answer

The elementary cellular automaton numbered 30 in Wolfram's catalogue. Every cell looks at (left, centre, right) and the eight outcomes follow 30's binary form 00011110 · equivalently, the new cell is left XOR (centre OR right). Each press of Step derives exactly one new row from the newest one.

Question 2

Why is Rule 30 famous?

Accepted Answer

Because two lines of arithmetic produce genuine chaos. Its centre column passes randomness tests and was used as the random-number source in early Mathematica, and essentially the same triangle pattern grows naturally on the shell of the Conus textile sea snail. It is the standard example that simple rules can generate endless complexity.

Question 3

How do I change the cascade?

Accepted Answer

Pick a starting row · the canonical single centre cell or a random row · then tap or click any column to flip a cell of the newest row (marked by the accent line). Press Play to run, Step to add one row, Reset to restore the current starting row, and drag the speed control up to a bounded maximum.

Question 4

Does the cascade grow forever?

Accepted Answer

The pattern does, but the memory does not. Only a fixed number of recent rows is kept on screen; once the window is full, the oldest row scrolls away as each new one arrives, while the generation counter keeps counting. You can leave it running as long as you like.

Question 5

Does it respect reduced motion and hidden tabs?

Accepted Answer

Yes. The simulation pauses itself whenever the tab is hidden, and if your device requests reduced motion it never auto-animates · you step rows by hand with the Step button or the Right arrow key instead, with the current state always visible.