A153911 - OEIS

A153911

Number of planar n X n X n binary triangular grids symmetric under 120 degree rotation with no more than 2 ones in any 3 X 3 X 3 subtriangle.

%I #5 Apr 28 2021 00:15:25

%S 1,2,412,3309,6170,28173,363650,995263,7017397,125707566,496907299,

%T 5084773943,131364083278,749724226722,10945594000512,414717014027555,

%U 3429998068477278,72977331677447737,3992874305065142952

%N Number of planar n X n X n binary triangular grids symmetric under 120 degree rotation with no more than 2 ones in any 3 X 3 X 3 subtriangle.

%K nonn

%O 0,2

%A _R. H. Hardin_, Jan 03 2009