cp's OEIS Frontend

A274896 Number of 4 X n 0..2 arrays with no element equal to any value at offset (0,-1) (-1,-1) or (-2,0) and new values introduced in order 0..2.

%I A274896 #8 Jan 31 2019 09:22:07
%S A274896 6,14,38,104,290,815,2291,6434,18065,50729,142469,400121,1123718,
%T A274896 3155882,8863073,24891350,69905726,196325636,551367590,1548479459,
%U A274896 4348802339,12213324374,34300315505,96330172385,270536931545,759785117405
%N A274896 Number of 4 X n 0..2 arrays with no element equal to any value at offset (0,-1) (-1,-1) or (-2,0) and new values introduced in order 0..2.
%H A274896 R. H. Hardin, <a href="/A274896/b274896.txt">Table of n, a(n) for n = 1..210</a>
%F A274896 Empirical: a(n) = 5*a(n-1) - 9*a(n-2) + 10*a(n-3) - 6*a(n-4) + a(n-5) for n>6.
%F A274896 Empirical g.f.: x*(6 - 16*x + 22*x^2 - 20*x^3 + 8*x^4 - x^5) / ((1 - x)*(1 - 4*x + 5*x^2 - 5*x^3 + x^4)). - _Colin Barker_, Jan 31 2019
%e A274896 Some solutions for n=4:
%e A274896 ..0..1..0..2. .0..1..2..0. .0..1..2..1. .0..1..0..2. .0..1..0..1
%e A274896 ..2..1..2..1. .0..1..2..0. .1..2..0..1. .2..1..0..1. .1..2..0..1
%e A274896 ..1..0..2..1. .1..2..0..1. .1..0..1..2. .2..0..2..1. .2..0..1..2
%e A274896 ..0..2..1..0. .1..2..0..1. .2..0..1..0. .1..0..1..0. .2..0..2..0
%Y A274896 Row 4 of A274895.
%K A274896 nonn
%O A274896 1,1
%A A274896 _R. H. Hardin_, Jul 10 2016