cp's OEIS Frontend

A184665 Number of (n+1) X 2 0..3 arrays with no 2 X 2 subblock summing to less than 6.

%I A184665 #9 Feb 27 2018 10:38:33
%S A184665 150,1740,19269,216912,2430631,27278035,305991368,3432961182,
%T A184665 38513146024,432071200891,4847297854288,54380688812185,
%U A184665 610083824961241,6844384156411424,76785501492801006,861438105302681684
%N A184665 Number of (n+1) X 2 0..3 arrays with no 2 X 2 subblock summing to less than 6.
%C A184665 Column 1 of A184673.
%H A184665 R. H. Hardin, <a href="/A184665/b184665.txt">Table of n, a(n) for n = 1..200</a>
%F A184665 Empirical: a(n) = 10*a(n-1) + 25*a(n-2) - 123*a(n-3) - 73*a(n-4) + 304*a(n-5) + 36*a(n-6) - 144*a(n-7).
%F A184665 Empirical g.f.: x*(150 + 240*x - 1881*x^2 - 828*x^3 + 4756*x^4 + 432*x^5 - 2304*x^6) / (1 - 10*x - 25*x^2 + 123*x^3 + 73*x^4 - 304*x^5 - 36*x^6 + 144*x^7). - _Colin Barker_, Feb 27 2018
%e A184665 Some solutions for 3 X 2:
%e A184665 ..0..1....0..0....2..0....2..1....3..2....0..2....1..3....3..1....3..0....3..1
%e A184665 ..2..3....3..3....3..3....2..1....1..3....3..3....3..1....3..1....2..3....3..3
%e A184665 ..0..1....2..0....3..3....1..2....2..2....2..1....3..1....3..1....2..1....1..0
%Y A184665 Cf. A184673.
%K A184665 nonn
%O A184665 1,1
%A A184665 _R. H. Hardin_, Jan 19 2011