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A208869 Number of nX5 0..3 arrays with new values 0..3 introduced in row major order and no element equal to more than one of its immediate leftward or upward or right-upward antidiagonal neighbors.

%I A208869 #7 Jul 22 2025 21:32:35
%S A208869 51,24472,14493405,8624977114,5134914951163,3057224057476808,
%T A208869 1820216057105650386,1083724145919960847502,645230025599333921071976,
%U A208869 384158448692090971917060268,228721088397696942173901117684
%N A208869 Number of nX5 0..3 arrays with new values 0..3 introduced in row major order and no element equal to more than one of its immediate leftward or upward or right-upward antidiagonal neighbors.
%C A208869 Column 5 of A208872
%H A208869 R. H. Hardin, <a href="/A208869/b208869.txt">Table of n, a(n) for n = 1..210</a>
%F A208869 Empirical: a(n) = 698*a(n-1) -64930*a(n-2) +2349972*a(n-3) -40985428*a(n-4) +382137700*a(n-5) -2071312484*a(n-6) +7427716824*a(n-7) -22247002672*a(n-8) +65755191408*a(n-9) -163887803568*a(n-10) +277785052512*a(n-11) -285817496832*a(n-12) +164238606720*a(n-13) -46819296000*a(n-14) +4897760256*a(n-15) for n>16
%e A208869 Some solutions for n=4
%e A208869 ..0..0..1..2..0....0..0..0..0..0....0..0..0..0..0....0..1..1..0..0
%e A208869 ..3..3..0..1..0....1..1..2..1..0....1..1..1..2..0....0..2..0..1..2
%e A208869 ..1..2..1..2..0....2..3..1..3..3....2..0..2..0..1....1..1..3..1..0
%e A208869 ..0..1..0..3..2....1..2..3..0..1....2..1..3..0..0....0..1..0..2..3
%K A208869 nonn
%O A208869 1,1
%A A208869 _R. H. Hardin_ Mar 02 2012