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A218523 Number of 2Xn arrays of the minimum value of corresponding elements and their horizontal or antidiagonal neighbors in a random 0..3 2Xn array.

%I A218523 #8 Jul 22 2025 23:58:00
%S A218523 16,36,286,1348,7902,42812,242438,1349524,7567448,42328892,237017542,
%T A218523 1326679924,7427188036,41577119948,232754004212,1302972323234,
%U A218523 7294158727224,40833303099488,228588363496794,1279657095800040
%N A218523 Number of 2Xn arrays of the minimum value of corresponding elements and their horizontal or antidiagonal neighbors in a random 0..3 2Xn array.
%C A218523 Row 2 of A218522
%H A218523 R. H. Hardin, <a href="/A218523/b218523.txt">Table of n, a(n) for n = 1..210</a>
%F A218523 Empirical: a(n) = 2*a(n-1) +17*a(n-2) +26*a(n-3) -19*a(n-4) -123*a(n-5) -138*a(n-6) -248*a(n-7) -329*a(n-8) +41*a(n-9) +1108*a(n-10) +1469*a(n-11) -54*a(n-12) -1158*a(n-13) -316*a(n-14) +144*a(n-15) +32*a(n-16)
%e A218523 Some solutions for n=3
%e A218523 ..2..1..1....0..0..2....0..0..3....0..0..3....3..2..2....0..0..1....2..0..0
%e A218523 ..1..1..3....2..0..0....1..1..2....1..1..3....3..2..2....0..0..2....1..0..0
%K A218523 nonn
%O A218523 1,1
%A A218523 _R. H. Hardin_ Oct 31 2012