A302011 - OEIS

%I #6 Apr 23 2021 11:31:23

%S 8,128,1808,25808,369040,5276816,75450768,1078839952,15425887120,

%T 220568403088,3153816694160,45095125134992,644796609413008,

%U 9219680980164752,131828418659815824,1884960228421653136

%N Number of 4 X n 0..1 arrays with every element equal to 0, 1, 2 or 3 horizontally or antidiagonally adjacent elements, with upper left element zero.

%C Row 4 of A302010.

%H R. H. Hardin, <a href="/A302011/b302011.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 13*a(n-1) +20*a(n-2) -16*a(n-3) -64*a(n-4) for n > 6.

%e Some solutions for n=5

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

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

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

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

%Y Cf. A302010.

%K nonn

%O 1,1

%A _R. H. Hardin_, Mar 30 2018