A196920 - OEIS

%I #5 Mar 31 2012 12:36:27

%S 1,9,58,335,2659,18354,123261,841565,5796373,40206133,280010220,

%T 1953475131,13643051451,95356664458,666849653893,4665205889379,

%U 32645573075339,228480724683384,1599269236394946,11195004310971415

%N Number of nX6 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 1,3,2,4,0 for x=0,1,2,3,4

%C Every 0 is next to 0 1's, every 1 is next to 1 3's, every 2 is next to 2 2's, every 3 is next to 3 4's, every 4 is next to 4 0's

%C Column 6 of A196922

%H R. H. Hardin, <a href="/A196920/b196920.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 11*a(n-1) -30*a(n-2) +34*a(n-3) -174*a(n-4) +374*a(n-5) -645*a(n-6) -1568*a(n-7) -3864*a(n-8) -2737*a(n-9) +19896*a(n-10) +39789*a(n-11) +53807*a(n-12) -25645*a(n-13) -97487*a(n-14) -31786*a(n-15) +356123*a(n-16) +927682*a(n-17) +716971*a(n-18) -1120870*a(n-19) -3680755*a(n-20) -3507819*a(n-21) +1342053*a(n-22) +7156543*a(n-23) +6759831*a(n-24) -751579*a(n-25) -7948456*a(n-26) -7605926*a(n-27) -1091182*a(n-28) +4551985*a(n-29) +4822652*a(n-30) +1470465*a(n-31) -1156354*a(n-32) -1454677*a(n-33) -488873*a(n-34) +58506*a(n-35) +204668*a(n-36) +24265*a(n-37) +17367*a(n-38) +2506*a(n-39) +1238*a(n-40) +3804*a(n-41) -6754*a(n-42) +876*a(n-43) -504*a(n-44) +432*a(n-45) for n>46

%e Some solutions for n=4

%e ..0..0..0..0..0..0....0..0..0..0..2..2....0..0..0..2..2..2....0..0..2..2..2..0

%e ..0..4..0..0..2..2....2..2..0..0..2..2....0..4..0..2..0..2....2..2..2..0..2..0

%e ..0..0..4..0..2..2....2..2..0..0..0..0....0..0..0..2..0..2....2..0..0..2..2..0

%e ..0..0..0..0..0..0....0..0..0..0..0..0....0..0..0..2..2..2....2..2..2..2..0..0

%K nonn

%O 1,2

%A _R. H. Hardin_ Oct 07 2011