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A254451 Number of (n+2)X(2+2) 0..1 arrays with every 3X3 subblock diagonal maximum minus antidiagonal median nondecreasing horizontally and vertically.

%I A254451 #6 Jul 23 2025 14:41:18
%S A254451 3036,26380,196684,1279568,8004340,48345120,289945200,1735438880,
%T A254451 10399188560,62416180384,375009286716,2254540612636,13558023603848,
%U A254451 81542178909476,490442432067776,2949842103362336,17742389731217108
%N A254451 Number of (n+2)X(2+2) 0..1 arrays with every 3X3 subblock diagonal maximum minus antidiagonal median nondecreasing horizontally and vertically.
%C A254451 Column 2 of A254457
%H A254451 R. H. Hardin, <a href="/A254451/b254451.txt">Table of n, a(n) for n = 1..210</a>
%F A254451 Empirical: a(n) = 9*a(n-1) -14*a(n-2) -44*a(n-3) +135*a(n-4) -59*a(n-5) -261*a(n-6) +1059*a(n-7) -122*a(n-8) -14896*a(n-9) +36367*a(n-10) -18563*a(n-11) -33563*a(n-12) +47849*a(n-13) -4574*a(n-14) -5864*a(n-15) -66679*a(n-16) +97131*a(n-17) -7175*a(n-18) -81255*a(n-19) +42242*a(n-20) +47504*a(n-21) -23099*a(n-22) -135393*a(n-23) +262392*a(n-24) -181030*a(n-25) -7740*a(n-26) +75060*a(n-27) +21756*a(n-28) +42676*a(n-29) -404560*a(n-30) +536056*a(n-31) -182368*a(n-32) -227200*a(n-33) +191776*a(n-34) -7296*a(n-35) +220032*a(n-36) -449664*a(n-37) +242688*a(n-38) +158208*a(n-39) -242176*a(n-40) +54272*a(n-41) -36864*a(n-42) +126976*a(n-43) -90112*a(n-44) -32768*a(n-45) +81920*a(n-46) -32768*a(n-47) for n>61
%e A254451 Some solutions for n=3
%e A254451 ..0..0..1..1....0..0..1..0....0..0..1..1....0..1..0..1....0..0..1..0
%e A254451 ..0..0..0..0....1..1..1..1....0..0..1..0....0..1..0..0....0..0..0..0
%e A254451 ..1..0..0..0....1..0..0..0....1..1..1..1....1..0..0..0....0..0..0..0
%e A254451 ..0..1..0..1....1..0..1..0....0..0..0..1....0..0..1..0....1..0..0..1
%e A254451 ..1..0..0..1....1..0..0..0....1..0..1..0....0..0..1..1....1..1..1..1
%K A254451 nonn
%O A254451 1,1
%A A254451 _R. H. Hardin_, Jan 30 2015