A316804 - OEIS

%I #4 Jul 14 2018 14:57:22

%S 8,128,1905,28248,420345,6256258,93109949,1385723098,20623265507,

%T 306929355068,4567929663745,67983009966484,1011769004146827,

%U 15057828687751316,224100761989675875,3335218680314293250

%N Number of nX4 0..1 arrays with every element unequal to 0, 1, 2, 3, 4, 5 or 6 king-move adjacent elements, with upper left element zero.

%C Column 4 of A316808.

%H R. H. Hardin, <a href="/A316804/b316804.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 15*a(n-1) -5*a(n-2) +50*a(n-3) -18*a(n-4) -81*a(n-5) +4*a(n-6) +20*a(n-7)

%e Some solutions for n=5

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

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

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

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

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

%Y Cf. A316808.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jul 14 2018