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A250970 Number of (n+1)X(5+1) 0..1 arrays with no 2X2 subblock having the sum of its diagonal elements less than the absolute difference of its antidiagonal elements.

%I A250970 #6 Jul 23 2025 12:55:30
%S A250970 2121,77537,2833397,103684186,3794909318,138900769559,5084110136919,
%T A250970 186091438754901,6811422962008298,249315542243292284,
%U A250970 9125588509861083659,334019954168148561523,12225987350399215480885,447502506618626972091831
%N A250970 Number of (n+1)X(5+1) 0..1 arrays with no 2X2 subblock having the sum of its diagonal elements less than the absolute difference of its antidiagonal elements.
%C A250970 Column 5 of A250973
%H A250970 R. H. Hardin, <a href="/A250970/b250970.txt">Table of n, a(n) for n = 1..210</a>
%F A250970 Empirical: a(n) = 64*a(n-1) -1446*a(n-2) +21783*a(n-3) -257090*a(n-4) +2364533*a(n-5) -17301630*a(n-6) +102437299*a(n-7) -484439145*a(n-8) +1808535109*a(n-9) -5311996643*a(n-10) +12229385847*a(n-11) -21849236431*a(n-12) +29285048520*a(n-13) -26153502129*a(n-14) +7239648236*a(n-15) +20967448076*a(n-16) -41791947829*a(n-17) +41249669536*a(n-18) -19653544893*a(n-19) -9216125179*a(n-20) +29489025257*a(n-21) -33624035531*a(n-22) +25340528985*a(n-23) -13860558578*a(n-24) +5642370770*a(n-25) -1727464741*a(n-26) +397748431*a(n-27) -68146076*a(n-28) +8635216*a(n-29) -707328*a(n-30) +35280*a(n-31)
%e A250970 Some solutions for n=2
%e A250970 ..0..0..1..0..0..0....1..0..1..0..1..0....0..1..1..0..1..1....1..1..1..1..1..1
%e A250970 ..0..1..1..0..1..1....1..1..0..0..1..0....1..1..0..1..0..1....1..1..0..1..0..0
%e A250970 ..1..0..1..0..1..0....1..0..0..1..0..0....1..0..1..0..1..1....0..0..1..0..0..0
%K A250970 nonn
%O A250970 1,1
%A A250970 _R. H. Hardin_, Nov 29 2014