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A209104 Number of 5Xn 0..2 arrays with new values 0..2 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 A209104 #7 Jul 22 2025 21:38:39
%S A209104 41,4568,407832,34538488,2896732704,242632290432,20321585350224,
%T A209104 1702054356798544,142558373809744128,11940239726878790824,
%U A209104 1000077375423933174600,83763383343364383999032
%N A209104 Number of 5Xn 0..2 arrays with new values 0..2 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 A209104 Row 5 of A209100
%H A209104 R. H. Hardin, <a href="/A209104/b209104.txt">Table of n, a(n) for n = 1..210</a>
%F A209104 Empirical: a(n) = 171*a(n-1) -10470*a(n-2) +325569*a(n-3) -5715687*a(n-4) +56148167*a(n-5) -245912801*a(n-6) -484495146*a(n-7) +10078833115*a(n-8) -31788474833*a(n-9) -62614662381*a(n-10) +560437441681*a(n-11) -642115987254*a(n-12) -2499011458897*a(n-13) +6268700558495*a(n-14) +963700261876*a(n-15) -12620524925764*a(n-16) +6372190291752*a(n-17) +1053712106560*a(n-18) -1060563638688*a(n-19) +11585781964416*a(n-20) +5647581956608*a(n-21) -36276070293504*a(n-22) +23488582508544*a(n-23) +1781937340416*a(n-24) -5735198490624*a(n-25) +1426902220800*a(n-26) for n>29
%e A209104 Some solutions for n=4
%e A209104 ..0..0..0..0....0..0..0..1....0..1..2..2....0..0..0..0....0..0..1..2
%e A209104 ..1..1..1..0....2..1..2..2....0..0..0..2....1..1..2..1....2..1..2..1
%e A209104 ..2..2..0..1....0..2..0..0....1..2..0..0....0..0..2..0....1..2..1..2
%e A209104 ..0..1..0..0....2..0..1..1....1..0..1..0....1..2..1..2....2..0..0..1
%e A209104 ..2..0..1..1....2..1..2..1....2..2..1..2....1..2..1..1....0..2..2..1
%K A209104 nonn
%O A209104 1,1
%A A209104 _R. H. Hardin_ Mar 05 2012