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A181220 Number of n X 4 binary matrices with no three 1's adjacent in a line horizontally, vertically, diagonally or antidiagonally.

%I A181220 #5 Apr 24 2021 09:36:46
%S A181220 13,169,1209,10732,97764,845531,7426986,65480503,574725752,5050028956,
%T A181220 44391722285,390072820213,3427866363455,30124436697657,
%U A181220 264728435711181,2326400950974628,20444198985083330,179661312288590309
%N A181220 Number of n X 4 binary matrices with no three 1's adjacent in a line horizontally, vertically, diagonally or antidiagonally.
%C A181220 Column 4 of A181224.
%H A181220 R. H. Hardin, <a href="/A181220/b181220.txt">Table of n, a(n) for n=1..275</a>
%F A181220 Empirical: a(n)=4*a(n-1)+27*a(n-2)+150*a(n-3)-59*a(n-4)-656*a(n-5)-2090*a(n-6)+4600*a(n-7)+558*a(n-8)-6222*a(n-9)+6935*a(n-10)-36512*a(n-11)+93343*a(n-12)-70961*a(n-13)+82681*a(n-14)-47047*a(n-15)-247244*a(n-16)+404537*a(n-17)-466677*a(n-18)+482071*a(n-19)-352513*a(n-20)+295888*a(n-21)-133016*a(n-22)+13672*a(n-23)-34436*a(n-24)+7664*a(n-25)+7816*a(n-26)+108*a(n-27)-620*a(n-28)-1024*a(n-29)+144*a(n-30)+32*a(n-31)+48*a(n-32).
%e A181220 Some avoided solutions for 3 X 4
%e A181220 ..0..1..0..1....1..0..0..0....0..0..1..0....1..0..0..0....0..0..0..1
%e A181220 ..0..0..1..0....1..0..0..0....0..0..1..1....0..1..0..0....0..1..0..1
%e A181220 ..0..1..0..0....1..1..0..0....0..0..1..0....1..0..1..0....0..0..0..1
%Y A181220 Cf. A181224.
%K A181220 nonn
%O A181220 1,1
%A A181220 _R. H. Hardin_ Oct 10 2010