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A201231 Number of nX4 0..3 arrays with every row and column running average nondecreasing rightwards and downwards, and the number of instances of each value within one of each other.

%I A201231 #7 Jul 22 2025 16:10:16
%S A201231 3,24,140,1028,7791,66027,508368,4293464,33177954,282310785,
%T A201231 2226471492,18845872240,149352193586,1252800269866,9919439949887,
%U A201231 82782378005253,656171911832714,5446960364973500,43213785216715427,357463895275500826
%N A201231 Number of nX4 0..3 arrays with every row and column running average nondecreasing rightwards and downwards, and the number of instances of each value within one of each other.
%C A201231 Column 4 of A201235
%H A201231 R. H. Hardin, <a href="/A201231/b201231.txt">Table of n, a(n) for n = 1..23</a>
%e A201231 Some solutions for n=6
%e A201231 ..0..0..0..0....0..0..0..1....0..0..0..1....0..0..0..0....0..0..0..0
%e A201231 ..0..1..2..1....0..1..1..1....0..0..0..2....0..1..1..1....0..0..3..1
%e A201231 ..0..1..2..3....0..3..3..2....1..1..1..2....0..3..2..3....2..2..2..3
%e A201231 ..1..1..3..2....0..3..2..2....1..3..2..3....1..3..2..2....1..2..3..2
%e A201231 ..3..3..3..3....1..3..2..2....1..2..3..2....1..3..2..2....1..1..3..2
%e A201231 ..1..2..2..2....1..3..2..3....2..3..3..3....1..3..2..3....1..1..3..3
%K A201231 nonn
%O A201231 1,1
%A A201231 _R. H. Hardin_ Nov 28 2011