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%I #15 Dec 03 2014 04:01:56
%S 1,2,4,24,352,10944,699136,89479168,22906494976,11728124051456,
%T 22906494976,11728124051456,12009599006670848,24595658764948865024,
%U 100743818301219142631424,825293359523586851364405248,13521606402434446949321074016256
%N Two-colorings of triangular arrays under rotational symmetries.
%H StackExchange, <a href="http://math.stackexchange.com/questions/772981/i-am-confused-on-how-to-solve-a-question-by-using-burnsides-lemma">two-colorings of triangular arrays</a>
%p Q:= proc(n)
%p if n mod 3 = 1 then 1/3*2^(1/2*n*(n + 1)) + 1/3*2^(2 + 1/6*(n - 1)*(n + 2))
%p else 1/3*2^(1/2*n*(n + 1)) + 1/3*2^(1 + 1/6*n*(n + 1))
%p end if
%p end proc
%K nonn
%O 1,2
%A _Marko Riedel_, Apr 28 2014