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%I #9 May 08 2018 06:19:34
%S 1,1,7,25,27,91,231,455,1135,2693,6041,14257,33349,76941,179553,
%T 418345,971503,2261807,5264419,12243481,28490729,66295633,154236017,
%U 358872825,835013523,1942797397,4520363539,10517663443,24471508585,56938341019
%N Number of n X 4 0..4 arrays with each element equal to the number its horizontal and vertical neighbors within one of itself.
%C Column 4 of A196017.
%H R. H. Hardin, <a href="/A196013/b196013.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = a(n-1) +2*a(n-2) +4*a(n-3) -a(n-4) -4*a(n-5) -2*a(n-6) -3*a(n-7) -3*a(n-8) +a(n-10) for n>14.
%F Empirical g.f.: x*(1 + 4*x^2 + 12*x^3 - 15*x^4 - 9*x^5 - x^6 - 8*x^7 + x^8 - 3*x^9 + 2*x^10+ 6*x^11 + 2*x^12 - 2*x^13) / (1 - x - 2*x^2 - 4*x^3 + x^4 + 4*x^5 + 2*x^6 + 3*x^7 + 3*x^8 - x^10). - _Colin Barker_, May 08 2018
%e Some solutions for n=5:
%e ..2..3..3..2....2..2..3..2....2..3..2..2....2..2..2..0....2..2..3..2
%e ..3..4..4..3....2..0..3..3....2..3..0..2....2..0..3..2....2..0..3..3
%e ..3..4..3..3....3..3..3..3....0..3..2..3....3..3..4..3....3..3..3..3
%e ..3..3..0..2....2..3..0..2....2..3..0..2....3..4..4..3....3..3..0..2
%e ..2..3..2..2....0..2..2..2....2..3..2..2....2..3..3..2....2..3..2..2
%Y Cf. A196017.
%K nonn
%O 1,3
%A _R. H. Hardin_, Sep 26 2011
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