cp's OEIS Frontend

A240285 Number of 2 X n 0..3 arrays with no element equal to one plus the sum of elements to its left or two plus the sum of the elements above it or zero plus the sum of the elements diagonally to its northwest, modulo 4.

%I A240285 #8 Oct 27 2018 06:22:28
%S A240285 2,8,19,76,181,741,1779,7308,17561,72140,173343,712043,1710905,
%T A240285 7027848,16886555,69364556,166669597,684625413,1645022411,6757226212,
%U A240285 16236307329,66693560300,160251722711,658262849419,1581678277825,6497028751792
%N A240285 Number of 2 X n 0..3 arrays with no element equal to one plus the sum of elements to its left or two plus the sum of the elements above it or zero plus the sum of the elements diagonally to its northwest, modulo 4.
%H A240285 R. H. Hardin, <a href="/A240285/b240285.txt">Table of n, a(n) for n = 1..210</a>
%F A240285 Empirical: a(n) = 12*a(n-2) - 24*a(n-4) + 31*a(n-6) - 16*a(n-8).
%F A240285 Empirical g.f.: x*(1 - x)*(2 + 10*x + 5*x^2 - 15*x^3 - 14*x^4 + 7*x^5 + 8*x^6) / (1 - 12*x^2 + 24*x^4 - 31*x^6 + 16*x^8). - _Colin Barker_, Oct 27 2018
%e A240285 Some solutions for n=4:
%e A240285 ..3..1..3..1....3..3..1..3....3..1..3..1....3..1..3..1....3..3..1..3
%e A240285 ..2..1..2..0....2..0..2..3....3..1..0..0....3..2..0..0....2..0..2..2
%Y A240285 Row 2 of A240284.
%K A240285 nonn
%O A240285 1,1
%A A240285 _R. H. Hardin_, Apr 03 2014