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A208636 Number of n X 7 0..1 arrays with new values 0..1 introduced in row major order and no element equal to more than one of its immediate leftward or upward or right-upward antidiagonal neighbors.

%I A208636 #9 Jul 05 2018 08:56:35
%S A208636 64,191,628,2149,7504,26508,94320,337227,1209736,4349981,15668332,
%T A208636 56505640,203961088,736686999,2662084284,9622940853,34793691400,
%U A208636 125826023972,455089068016,1646125164451,5954682909712,21541486064685
%N A208636 Number of n X 7 0..1 arrays with new values 0..1 introduced in row major order and no element equal to more than one of its immediate leftward or upward or right-upward antidiagonal neighbors.
%C A208636 Column 7 of A208637.
%H A208636 R. H. Hardin, <a href="/A208636/b208636.txt">Table of n, a(n) for n = 1..210</a>
%F A208636 Empirical: a(n) = 8*a(n-1) - 21*a(n-2) + 20*a(n-3) - 5*a(n-4).
%F A208636 Empirical g.f.: x*(64 - 321*x + 444*x^2 - 144*x^3) / ((1 - 3*x + x^2)*(1 - 5*x + 5*x^2)). - _Colin Barker_, Jul 05 2018
%e A208636 Some solutions for n=4:
%e A208636 ..0..1..0..0..0..0..1....0..1..1..0..0..1..0....0..0..1..0..1..1..0
%e A208636 ..1..0..1..1..1..0..0....0..0..1..1..0..1..1....1..0..1..0..0..1..0
%e A208636 ..0..1..0..0..1..1..1....1..0..0..1..0..0..1....0..1..0..1..0..1..0
%e A208636 ..1..0..1..0..0..0..0....0..1..0..1..1..0..0....1..0..1..0..1..0..1
%Y A208636 Cf. A208637.
%K A208636 nonn
%O A208636 1,1
%A A208636 _R. H. Hardin_, Feb 29 2012