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%I #13 Feb 04 2015 16:09:18
%S 1,1,5,5,17,9,21,21,25,33,45,49,81,69,105,81,101,101,165,141,197,185,
%T 217,209,265,245,337,269,405,325,477,389,521,461,625,469,621,485,769,
%U 585,849,737,825,705,973,713,985,841,1089,925,1257,969,1229,1093,1265
%N a(n) = if n is even, number of ON cells at stage n of two-dimensional 5-neighbor outer totalistic cellular automaton defined by "Rule 461" or if n is odd, number of OFF cells.
%D S. Wolfram, A New Kind of Science, Wolfram Media, 2002; pp. 173-175.
%H N. J. A. Sloane, <a href="/A246329/a246329.pdf">Illustration of first 24 generations</a>
%H <a href="/index/Ce#cell">Index entries for sequences related to cellular automata</a>
%t Map[Function[Apply[Plus, Flatten[ #1]]], CellularAutomaton[{ 461, {2, {{0, 2, 0}, {2, 1, 2}, {0, 2, 0}}}, {1, 1}}, {{{1}}, 0}, 130]] (* then subtract the odd-indexed terms from 131^2 *)
%t ArrayPlot /@ CellularAutomaton[{461, {2, {{0, 2, 0}, {2, 1, 2}, {0, 2, 0}}}, {1, 1}}, {{{1}}, 0}, 23]
%Y A246329 is a bisection.
%Y Cf. A169699, A246316, A246318, A246325, A246326, ...
%K nonn
%O 0,3
%A _N. J. A. Sloane_, Aug 30 2014