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%I #5 Mar 31 2012 12:36:29
%S 1,8,46,231,1221,6284,32754,170928,888997,4628482,24105642,125519823,
%T 653563458,3403159865,17720701794,92272812665,480470439059,
%U 2501848357281,13027318240407,67834213566454,353217871857983,1839232324012492
%N Number of nX4 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 4,3,2,1,2 for x=0,1,2,3,4
%C Every 0 is next to 0 4's, every 1 is next to 1 3's, every 2 is next to 2 2's, every 3 is next to 3 1's, every 4 is next to 4 2's
%C Column 4 of A197242
%H R. H. Hardin, <a href="/A197238/b197238.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 3*a(n-1) +4*a(n-2) +36*a(n-3) +26*a(n-4) -228*a(n-6) -184*a(n-7) -403*a(n-8) -173*a(n-9) -80*a(n-10) +149*a(n-11) +26*a(n-12) +297*a(n-13) -1359*a(n-14) -769*a(n-15) +2039*a(n-16) +741*a(n-17) -976*a(n-18) +22*a(n-19) +962*a(n-20) +281*a(n-21) -2642*a(n-22) -3738*a(n-23) +689*a(n-24) +4813*a(n-25) +2462*a(n-26) -2068*a(n-27) -1942*a(n-28) +1113*a(n-29) +1865*a(n-30) +372*a(n-31) -577*a(n-32) -416*a(n-33) -64*a(n-34) +44*a(n-35) +24*a(n-36) +4*a(n-37)
%e Some solutions containing all values 0 to 4 for n=5
%e ..0..2..2..2....1..3..1..0....1..0..0..0....0..1..0..0....0..2..2..2
%e ..0..2..4..2....0..1..0..0....3..1..0..0....1..3..1..0....0..2..4..2
%e ..1..2..2..2....0..2..2..2....1..2..2..2....2..2..2..0....0..2..2..2
%e ..3..1..1..0....0..2..4..2....0..2..4..2....2..4..2..0....1..3..1..0
%e ..1..1..3..1....0..2..2..2....0..2..2..2....2..2..2..0....0..1..0..0
%K nonn
%O 1,2
%A _R. H. Hardin_ Oct 12 2011
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