A367054 Number of iterations until a repeating cycle begins in rule 161 cellular automaton in a cyclic universe of circumference n starting with one cell on.

0, 0, 2, 0, 0, 4, 4, 0, 0, 2, 2, 0, 0, 8, 8, 0, 0, 2, 2, 0, 0, 4, 4, 0, 0, 2, 2, 0, 0, 16, 16, 0, 0, 2, 2, 0, 0, 4, 4, 0, 0, 2, 2, 0, 0, 8, 8, 0, 0, 2, 2, 0, 0, 4, 4, 0, 0, 2, 2, 0, 0, 32, 32, 0, 0, 2, 2, 0, 0, 4, 4, 0, 0, 2, 2, 0, 0, 8, 8, 0, 0, 2, 2, 0, 0, 4, 4, 0, 0, 2, 2

Offset: 1

Author

Angelo Rosso, Nov 03 2023

Keywords

• nonn

Examples

			For n = 2 we have: 10 -> 01 -> 10; since the cycle started from the 0th iteration, a(2) = 0.
For n = 3 we have: 100 -> 000 -> 111 -> 111; since the cycle started from the 2nd iteration, a(3) = 2.
		

Crossrefs

Cf. A334506, A000029.