A269056 - OEIS

%I #4 Feb 18 2016 11:41:52

%S 243,2430,17346,183072,1643376,15547380,140497512,1273499256,

%T 11354964888,100764874440,886829123676,7765850889120,67643548943508,

%U 586749197487720,5069733374448192,43657996370224608,374818434125094900

%N Number of 5Xn 0..2 arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling two not more than once.

%C Row 5 of A269052.

%H R. H. Hardin, <a href="/A269056/b269056.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 12*a(n-1) +26*a(n-2) -566*a(n-3) -123*a(n-4) +8804*a(n-5) -4121*a(n-6) -59620*a(n-7) +55115*a(n-8) +183692*a(n-9) -256127*a(n-10) -211910*a(n-11) +498819*a(n-12) -48036*a(n-13) -371692*a(n-14) +214008*a(n-15) +43848*a(n-16) -64656*a(n-17) +8640*a(n-18) +5184*a(n-19) -1296*a(n-20) for n>22

%e Some solutions for n=4

%e ..0..1..2..1. .1..0..1..0. .0..1..2..1. .0..0..1..0. .1..1..0..0

%e ..2..1..2..1. .0..0..1..2. .0..1..0..1. .1..2..1..2. .0..0..0..0

%e ..2..1..0..2. .1..0..1..2. .0..1..2..1. .2..2..2..2. .0..0..0..1

%e ..0..1..2..1. .0..0..1..0. .0..1..0..0. .2..1..2..1. .0..0..0..1

%e ..0..1..2..2. .0..0..1..0. .0..0..0..0. .0..1..2..2. .1..0..0..1

%Y Cf. A269052.

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 18 2016