login
Number of nX2 0..1 arrays with every element equal to 0, 2, 4, 5 or 7 king-move adjacent elements, with upper left element zero.
1

%I #4 Jan 22 2018 06:12:56

%S 1,4,4,8,36,52,100,356,628,1220,3668,7268,14516,38980,82452,169508,

%T 423284,926980,1953236,4661476,10384180,22302148,51781012,116208548,

%U 253089012,578128516,1300672852,2860550756,6473222836,14566091588

%N Number of nX2 0..1 arrays with every element equal to 0, 2, 4, 5 or 7 king-move adjacent elements, with upper left element zero.

%C Column 2 of A298575.

%H R. H. Hardin, <a href="/A298569/b298569.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) +8*a(n-3) -4*a(n-4)

%e Some solutions for n=5

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

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

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

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

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

%Y Cf. A298575.

%K nonn

%O 1,2

%A _R. H. Hardin_, Jan 22 2018