A281606 - OEIS

%I #4 Jan 25 2017 10:41:35

%S 5,50,209,1283,8180,49572,302304,1849212,11295326,69003066,421598546,

%T 2575763454,15736620000,96143466614,587391366384,3588683849428,

%U 21925168436114,133952450888038,818386359248384,4999955088202190

%N Number of 3Xn 0..2 arrays with no element equal to more than one of its horizontal, diagonal or antidiagonal neighbors and with new values introduced in order 0 sequentially upwards.

%C Row 3 of A281605.

%H R. H. Hardin, <a href="/A281606/b281606.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 6*a(n-1) -4*a(n-2) +29*a(n-3) -15*a(n-4) +73*a(n-5) +11*a(n-6) -32*a(n-7) +6*a(n-8) +a(n-9) -30*a(n-10) -26*a(n-11) +10*a(n-12) +8*a(n-13) for n>15

%e Some solutions for n=4

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

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

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

%Y Cf. A281605.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jan 25 2017