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A254169 Number of (2+2)X(n+2) 0..1 arrays with every 3X3 subblock diagonal maximum minus antidiagonal median nondecreasing horizontally, vertically and ne-to-sw antidiagonally.

%I A254169 #6 Jul 23 2025 14:29:37
%S A254169 3036,23660,164408,1078032,6831024,41678024,251430924,1509107876,
%T A254169 9050890564,54337026684,326446356700,1962472283332,11801023646284,
%U A254169 70973760221804,426874983655444,2567503678416152,15442742976914288
%N A254169 Number of (2+2)X(n+2) 0..1 arrays with every 3X3 subblock diagonal maximum minus antidiagonal median nondecreasing horizontally, vertically and ne-to-sw antidiagonally.
%C A254169 Row 2 of A254168
%H A254169 R. H. Hardin, <a href="/A254169/b254169.txt">Table of n, a(n) for n = 1..210</a>
%F A254169 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 A254169 Some solutions for n=3
%e A254169 ..0..0..0..1..0....0..1..1..1..1....0..0..1..1..0....0..0..0..0..0
%e A254169 ..1..0..1..0..0....1..1..0..0..0....1..0..1..1..1....1..1..1..1..1
%e A254169 ..1..1..0..0..0....1..0..0..1..0....1..0..0..0..0....1..1..1..0..0
%e A254169 ..0..1..1..1..1....0..1..0..1..1....1..0..0..1..1....0..1..1..0..1
%K A254169 nonn
%O A254169 1,1
%A A254169 _R. H. Hardin_, Jan 26 2015