A270054 - OEIS

%I #4 Mar 09 2016 07:11:38

%S 240,99840,22911300,4410058320,779206497960,130850370606120,

%T 21244602958557060,3367363526042121600,524230216822482202860,

%U 80480015854082855624040,12218158166851049001563640

%N Number of nX4 0..4 arrays with some element plus some horizontally or vertically adjacent neighbor totalling four exactly once.

%C Column 4 of A270058.

%H R. H. Hardin, <a href="/A270054/b270054.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 306*a(n-1) -27803*a(n-2) +685150*a(n-3) -6795613*a(n-4) +28270996*a(n-5) -41396356*a(n-6) for n>7

%e Some solutions for n=2

%e ..2..4..2..1. .3..2..1..0. .1..3..4..1. .2..0..0..3. .1..2..3..0

%e ..4..4..0..0. .4..3..2..2. .0..2..1..1. .0..3..2..2. .3..4..3..3

%Y Cf. A270058.

%K nonn

%O 1,1

%A _R. H. Hardin_, Mar 09 2016