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A208405 Number of nX5 0..3 arrays with new values 0..3 introduced in row major order and no element equal to more than two of its immediate leftward or upward or right-upward antidiagonal neighbors.

%I A208405 #7 Jul 22 2025 21:19:54
%S A208405 51,41914,40883360,40039156736,39216100214432,38410047476679936,
%T A208405 37620564383817645696,36847308431734650845696,
%U A208405 36089946042522268966513152,35348150537672718536490582016,34621601954234065647421901637632
%N A208405 Number of nX5 0..3 arrays with new values 0..3 introduced in row major order and no element equal to more than two of its immediate leftward or upward or right-upward antidiagonal neighbors.
%C A208405 Column 5 of A208408
%H A208405 R. H. Hardin, <a href="/A208405/b208405.txt">Table of n, a(n) for n = 1..210</a>
%F A208405 Empirical: a(n) = 1008*a(n-1) -28108*a(n-2) +138160*a(n-3) -223680*a(n-4) +168192*a(n-5) -55296*a(n-6) for n>7
%e A208405 Some solutions for n=4
%e A208405 ..0..0..1..0..2....0..0..0..0..0....0..0..0..1..2....0..0..1..0..0
%e A208405 ..3..1..0..0..1....0..1..0..2..2....3..2..0..1..2....1..1..0..1..0
%e A208405 ..1..1..1..2..2....2..2..3..2..2....1..1..1..0..2....0..1..1..0..2
%e A208405 ..3..0..3..3..0....3..1..1..2..1....1..3..3..1..2....1..2..1..0..3
%K A208405 nonn
%O A208405 1,1
%A A208405 _R. H. Hardin_ Feb 26 2012