A318071 - OEIS

%I #4 Aug 15 2018 13:18:18

%S 8,20,41,73,149,372,861,2016,4901,11698,27986,67359,161518,387556,

%T 930666,2233451,5360842,12868595,30887501,74139733,177960357,

%U 427157604,1025312853,2461074852,5907342192,14179472548,34035173339,81695041734

%N Number of nX4 0..1 arrays with every element unequal to 0, 1, 2 or 5 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

%C Column 4 of A318075.

%H R. H. Hardin, <a href="/A318071/b318071.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 2*a(n-1) +a(n-2) +2*a(n-3) -3*a(n-4) -5*a(n-5) -2*a(n-7) +7*a(n-8) -a(n-9) -2*a(n-10) +8*a(n-11) -3*a(n-12) -a(n-13) -3*a(n-14) -3*a(n-15) +4*a(n-16) +a(n-17) -a(n-18) for n>21

%e Some solutions for n=5

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

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

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

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

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

%Y Cf. A318075.

%K nonn

%O 1,1

%A _R. H. Hardin_, Aug 15 2018