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A236805 Number of (n+1)X(4+1) 0..2 arrays with the maximum plus the lower median minus the upper median minus the minimum of every 2X2 subblock equal.

%I A236805 #6 Jul 23 2025 09:34:21
%S A236805 4183,60187,929447,16530709,270610375,5140896385,86863046591,
%T A236805 1730194335025,29809824906343,613527734331097,10689124490322287,
%U A236805 224961906203697169,3943143681821693815,84279362890540754665
%N A236805 Number of (n+1)X(4+1) 0..2 arrays with the maximum plus the lower median minus the upper median minus the minimum of every 2X2 subblock equal.
%C A236805 Column 4 of A236809
%H A236805 R. H. Hardin, <a href="/A236805/b236805.txt">Table of n, a(n) for n = 1..210</a>
%F A236805 Empirical: a(n) = 36*a(n-1) +213*a(n-2) -20688*a(n-3) +159340*a(n-4) +2245440*a(n-5) -34534356*a(n-6) +121902336*a(n-7) +49292928*a(n-8) -974576448*a(n-9) +1350053568*a(n-10) +778781952*a(n-11) -2623560192*a(n-12) +1330255872*a(n-13)
%e A236805 Some solutions for n=2
%e A236805 ..0..1..0..2..2....0..0..2..0..1....0..1..1..1..1....1..0..1..2..2
%e A236805 ..2..0..0..1..0....1..2..1..2..0....1..1..2..1..0....0..0..2..0..1
%e A236805 ..2..1..0..0..0....0..0..0..0..1....1..0..2..0..0....1..0..1..2..0
%K A236805 nonn
%O A236805 1,1
%A A236805 _R. H. Hardin_, Jan 31 2014