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A131957 Busy Beaver sigma variation: maximum number of 1's on the final tape, for a 2-state, 2-symbol Turing machine running on a tape which is initialized with the number n in binary and 0's everywhere else. The machine is started at the rightmost bit in the number n.

%I A131957 #14 Feb 16 2025 08:33:06
%S A131957 4,4,4,5,6,6,5,6,5,6,6,7,6,7,6,7,6,7,6,6,8,8,7,8,6,7,7,8,7,8,7,8,7,8,
%T A131957 6,8,7,7,7,7,6,8,8,9,8,9,8,10,7,8,7,7,7,9,8,9,7,8,8,9,8,9,8,9,8,9,8,8,
%U A131957 8,7,8,10,8,7,7,8,8,8,7,8,8,8,7,10,10,10,9,10,8,10,10,10,10,10,9,12,8,9,7,9
%N A131957 Busy Beaver sigma variation: maximum number of 1's on the final tape, for a 2-state, 2-symbol Turing machine running on a tape which is initialized with the number n in binary and 0's everywhere else. The machine is started at the rightmost bit in the number n.
%H A131957 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/BusyBeaver.html">Busy Beaver</a>
%e A131957 a(5) is the maximum number of 1's on a tape which is initialized as:
%e A131957 ..000001010000.... with the machine starting at the rightmost 1.
%e A131957 a(5) = 6, with the machine:
%e A131957 A0-> 1BL
%e A131957 A1-> 1AR
%e A131957 B0-> 1*L
%e A131957 B1-> 1AL
%Y A131957 Cf. A060843, A131956.
%K A131957 nonn
%O A131957 0,1
%A A131957 Bryan Jacobs (bryanjj(AT)gmail.com), Aug 01 2007