A153924 - OEIS

%I #5 Apr 28 2021 00:16:51

%S 1,2,50178,330289,4142724,38758787,721406196,10013654728,271477291887,

%T 5511387919570,217444939703686,6427549653424203,370935313492909781

%N Number of planar n X n X n binary triangular grids with mirror symmetry about one altitude with no more than 3 ones in any 4 X 4 X 4 subtriangle.

%K nonn

%O 0,2

%A _R. H. Hardin_, Jan 03 2009