cp's OEIS Frontend

A241055 Number of 2 X n 0..3 arrays with no element equal to one plus the sum of elements to its left or zero plus the sum of the elements above it or zero 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 A241055 #7 Oct 29 2018 10:05:00
%S A241055 2,3,2,10,18,18,46,58,102,173,264,487,738,1318,2151,3591,6192,10096,
%T A241055 17480,28925,49131,82966,138977,236535,395979,671706,1131018,1908201,
%U A241055 3226558,5432423,9189152,15486612,26156656,44151446,74485403,125808822
%N A241055 Number of 2 X n 0..3 arrays with no element equal to one plus the sum of elements to its left or zero plus the sum of the elements above it or zero 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 A241055 R. H. Hardin, <a href="/A241055/b241055.txt">Table of n, a(n) for n = 1..210</a>
%F A241055 Empirical: a(n) = 3*a(n-2) + 3*a(n-3) - 3*a(n-4) - 4*a(n-5) - 2*a(n-6) + 3*a(n-7) - a(n-9) + 2*a(n-11) - 2*a(n-12) + 2*a(n-15) for n>17.
%F A241055 Empirical g.f.: x*(2 + 3*x - 4*x^2 - 5*x^3 + 9*x^4 - x^5 - 16*x^6 - 12*x^7 - x^8 + 3*x^9 + 3*x^10 + 11*x^12 - 10*x^13 - 8*x^14 + 6*x^15 + 8*x^16) / ((1 - x)*(1 + x - 2*x^2 - 5*x^3 - 2*x^4 + 2*x^5 + 4*x^6 + x^7 + x^8 + 2*x^9 + 2*x^10 + 2*x^12 + 2*x^13 + 2*x^14)). - _Colin Barker_, Oct 29 2018
%e A241055 Some solutions for n=4:
%e A241055 ..3..3..2..2....3..3..2..2....3..2..3..3....3..2..3..3....3..3..2..2
%e A241055 ..2..1..1..3....2..2..0..0....2..1..1..0....2..1..1..2....2..2..0..3
%Y A241055 Row 2 of A241054.
%K A241055 nonn
%O A241055 1,1
%A A241055 _R. H. Hardin_, Apr 15 2014