cp's OEIS Frontend

A239594 Number of n X 2 0..3 arrays with no element equal to zero plus the sum of elements to its left or one plus the sum of elements above it or one plus the sum of the elements diagonally to its northwest or one plus the sum of the elements antidiagonally to its northeast, modulo 4.

%I A239594 #7 Oct 26 2018 09:24:27
%S A239594 4,3,4,4,5,7,8,11,12,16,19,24,30,36,46,55,70,85,106,131,161,201,246,
%T A239594 307,377,468,578,714,885,1091,1353,1669,2067,2554,3158,3907,4827,5974,
%U A239594 7381,9132,11288,13959,17262,21340,26394,32628,40353,49890,61693,76284,94321
%N A239594 Number of n X 2 0..3 arrays with no element equal to zero plus the sum of elements to its left or one plus the sum of elements above it or one plus the sum of the elements diagonally to its northwest or one plus the sum of the elements antidiagonally to its northeast, modulo 4.
%H A239594 R. H. Hardin, <a href="/A239594/b239594.txt">Table of n, a(n) for n = 1..210</a>
%F A239594 Empirical: a(n) = a(n-2) + a(n-5) for n>6.
%F A239594 Empirical g.f.: x*(4 + 3*x + x^3 + x^4 - x^5) / (1 - x^2 - x^5). - _Colin Barker_, Oct 26 2018
%e A239594 All solutions for n=4:
%e A239594 ..2..0....2..0....3..0....2..0
%e A239594 ..2..0....2..0....2..3....2..0
%e A239594 ..3..0....2..0....3..2....3..0
%e A239594 ..2..3....2..0....2..3....3..2
%Y A239594 Column 2 of A239599.
%K A239594 nonn
%O A239594 1,1
%A A239594 _R. H. Hardin_, Mar 22 2014