A295647 - OEIS

%I #4 Nov 25 2017 08:35:32

%S 7,35,184,956,4993,26037,135848,708695,3697224,19288127,100624816,

%T 524952380,2738639019,14287283144,74535731534,388847564661,

%U 2028589853186,10583007752168,55210792323272,288030743269151,1502635727144728

%N Number of nX3 0..1 arrays with each 1 horizontally or vertically adjacent to 0, 1, 3 or 4 1s.

%C Column 3 of A295652.

%H R. H. Hardin, <a href="/A295647/b295647.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 5*a(n-1) +3*a(n-2) -9*a(n-3) -a(n-4) -13*a(n-5) -11*a(n-6) -8*a(n-7) +37*a(n-8) +30*a(n-9) -31*a(n-10) +29*a(n-11) -4*a(n-12) +a(n-13) -8*a(n-14) +4*a(n-15) -7*a(n-16) +a(n-17) -a(n-18)

%e Some solutions for n=7

%e ..1..0..0. .0..1..0. .0..0..0. .0..0..0. .1..0..0. .1..0..0. .1..0..1

%e ..0..0..0. .1..0..0. .0..1..0. .0..1..0. .0..0..0. .0..1..0. .0..0..1

%e ..0..0..1. .0..1..1. .1..1..1. .1..1..0. .0..1..0. .1..0..0. .0..0..0

%e ..0..0..1. .0..0..0. .0..1..0. .0..1..0. .0..0..1. .1..0..1. .0..0..1

%e ..0..1..0. .0..0..0. .0..0..1. .0..0..1. .0..0..0. .0..1..0. .0..1..1

%e ..1..0..0. .1..0..0. .0..0..1. .1..0..0. .0..0..0. .0..0..1. .0..0..1

%e ..0..1..1. .1..0..1. .1..1..0. .1..0..1. .0..1..1. .0..0..0. .0..1..0

%Y Cf. A295652.

%K nonn

%O 1,1

%A _R. H. Hardin_, Nov 25 2017