%I #6 Sep 03 2022 20:41:00
%S 4,141,25169,16941289,40820607681,350983455561087,
%T 10767951776455515799,1178739099906082214413048,
%U 460405515303453536692441783335,641654973151502496777935760164666385
%N Number of (n+1) X (n+1) 0..3 symmetric matrices with every 2 X 2 subblock having two or three distinct values, and new values 0..3 introduced in lower triangle row major order.
%e Some solutions for n=3
%e ..0..1..2..3....0..1..1..1....0..1..2..1....0..0..1..0....0..1..2..2
%e ..1..1..3..1....1..2..2..3....1..2..2..2....0..1..2..1....1..1..3..3
%e ..2..3..0..0....1..2..0..3....2..2..1..0....1..2..2..3....2..3..3..0
%e ..3..1..0..3....1..3..3..0....1..2..0..2....0..1..3..2....2..3..0..3
%K nonn
%O 1,1
%A _R. H. Hardin_, Mar 27 2012
