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%I #8 Feb 25 2023 18:06:51
%S 1,2,1,1,3,2,2,7,3,6,15,12,17,63,47,86,272,269,423,2020,1609,3902,
%T 14951,18193,36083,200112,201396,575152,2652677,3907855,9200561
%N Number of planar n X n X n binary triangular grids symmetric both under 120-degree rotation and reflection with no more than 1 one in any 3 X 3 X 3 subtriangle.
%K nonn
%O 0,2
%A _R. H. Hardin_, Jan 03 2009