cp's OEIS Frontend

A239406 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, modulo 4.

%I A239406 #7 Oct 26 2018 08:59:07
%S A239406 5,23,105,478,2165,9811,44399,201006,909679,4117547,18635613,84347726,
%T A239406 381758761,1727876419,7820451787,35395951502,160204196803,
%U A239406 725095175067,3281826924665,14853766696750,67229111585533,304283379907315
%N A239406 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, modulo 4.
%H A239406 R. H. Hardin, <a href="/A239406/b239406.txt">Table of n, a(n) for n = 1..210</a>
%F A239406 Empirical: a(n) = 3*a(n-1) + 12*a(n-2) - 18*a(n-3) - 29*a(n-4) + 19*a(n-5) + 38*a(n-6) + 8*a(n-7).
%F A239406 Empirical g.f.: x*(5 + 8*x - 24*x^2 - 23*x^3 + 30*x^4 + 42*x^5 + 8*x^6) / (1 - 3*x - 12*x^2 + 18*x^3 + 29*x^4 - 19*x^5 - 38*x^6 - 8*x^7). - _Colin Barker_, Oct 26 2018
%e A239406 Some solutions for n=5:
%e A239406 ..3..3..1..3..0....3..1..0..0..3....0..0..3..1..3....3..3..0..0..0
%e A239406 ..0..2..0..0..0....2..0..1..1..3....3..3..2..2..2....2..0..0..1..3
%Y A239406 Row 2 of A239405.
%K A239406 nonn
%O A239406 1,1
%A A239406 _R. H. Hardin_, Mar 17 2014