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%I #13 Feb 18 2015 07:53:46
%S 4,8,12,16,24,32,52,40,56,72,72,92,128,140,136,160,152,200,244,236,
%T 264,232,268,360,316,416,320,384,436,412,500,492,500,524,680,584,744,
%U 700,764,884,896,748,1056,864,888,992,1036,1060,1296,1268,1436,1408,1472
%N Cell populations in the development of the 2 X 2 square with the 2D cellular automaton rule seeds (/2).
%H Eric M. Schmidt, <a href="/A097981/b097981.txt">Table of n, a(n) for n = 0..1000</a>
%H Eric M. Schmidt, <a href="/A097981/a097981.cpp.txt">C++ code to compute this sequence</a>
%H Mirek Wojtowicz, <a href="http://www.mirekw.com/ca/">Information on many 2D cellular automata</a>
%H <a href="/index/Ce#cell">Index entries for sequences related to cellular automata</a>
%e a(0) = 4 because the 2 X 2 square contains 4 cells. a(1) = 8 because 8 cells are neighbors of exactly 2 of the original 4 cells. a(2) = 12 because 12 cells are neighbors of exactly 2 of the previous 8 cells.
%Y Cf. A097995, A097996.
%K nonn
%O 0,1
%A _Oliver Pechenik_, Sep 07 2004
%E Offset changed by _Eric M. Schmidt_, Mar 10 2013