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A228280 Number of nX5 binary arrays with top left value 1 and no two ones adjacent horizontally, vertically or nw-se diagonally.

%I A228280 #23 Jun 13 2015 00:54:43
%S A228280 5,13,112,587,3631,21166,126119,745178,4416695,26150120,154877307,
%T A228280 917205757,5431915952,32169045631,190512481196,1128258633821,
%U A228280 6681806858103,39571194265886,234349700556332,1387872742075595
%N A228280 Number of nX5 binary arrays with top left value 1 and no two ones adjacent horizontally, vertically or nw-se diagonally.
%C A228280 Column 5 of A228285.
%H A228280 R. H. Hardin, <a href="/A228280/b228280.txt">Table of n, a(n) for n = 1..210</a>
%H A228280 <a href="/index/Rec#order_13">Index entries for linear recurrences with constant coefficients</a>, signature (1, 21, 48, 14, -69, -38, 68, 13, -57, 37, -8, -2, 1).
%F A228280 a(n) = a(n-1) +21*a(n-2) +48*a(n-3) +14*a(n-4) -69*a(n-5) -38*a(n-6) +68*a(n-7) +13*a(n-8) -57*a(n-9) +37*a(n-10) -8*a(n-11) -2*a(n-12) +a(n-13)
%F A228280 G.f.: x*(5 + 8*x - 6*x^2 - 38*x^3 - 2*x^4 - 5*x^5 + 45*x^6 - 51*x^7 + 26*x^8 - 4*x^9 - 2*x^10 + x^11)/((1 + 2*x - 2*x^3 + x^4)*(1 - 3*x - 15*x^2 - 16*x^3 + 11*x^4 + 20*x^5 - 19*x^6 + 8*x^7 - x^9)). - _M. F. Hasler_, Apr 27 2014
%e A228280 Some solutions for n=4
%e A228280 ..1..0..1..0..0....1..0..0..0..0....1..0..1..0..0....1..0..0..0..0
%e A228280 ..0..0..0..0..0....0..0..0..1..0....0..0..0..0..0....0..0..0..0..1
%e A228280 ..0..0..0..1..0....0..0..0..0..0....0..1..0..1..0....0..1..0..1..0
%e A228280 ..0..1..0..0..0....0..0..1..0..1....1..0..0..0..0....1..0..0..0..0
%Y A228280 See A228277-A228285, especially the latter.
%Y A228280 See also the k=5 variants of A228390, A228476, A228506 etc.
%K A228280 nonn
%O A228280 1,1
%A A228280 _R. H. Hardin_ Aug 19 2013
%E A228280 Edited by _N. J. A. Sloane_, Aug 22 2013