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%I #5 Mar 31 2012 12:36:34
%S 17,2452,413375,72559212,12940532183,2322145946560,417688220022251,
%T 75197892524349728,13542776983363615379,2439305921057059368196,
%U 439386062130801234903655,79146996287674677581757652
%N Number of 2nX4 0..3 arrays with values 0..3 introduced in row major order and each element equal to exactly one horizontal and vertical neighbor
%C Column 2 of A198290
%H R. H. Hardin, <a href="/A198288/b198288.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = 341*a(n-1) -38970*a(n-2) +2135218*a(n-3) -67448667*a(n-4) +1375490159*a(n-5) -19754442612*a(n-6) +216233988876*a(n-7) -1930500555319*a(n-8) +14641614117891*a(n-9) -95232147538058*a(n-10) +525211971434290*a(n-11) -2391181584630749*a(n-12) +8566626104248057*a(n-13) -21804187934100424*a(n-14) +26325592371676176*a(n-15) +62458261081740144*a(n-16) -409636534740954048*a(n-17) +948362811460747776*a(n-18) -580420633538230272*a(n-19) -2477378037254639616*a(n-20) +6262481237853487104*a(n-21) -5586587527536967680*a(n-22) +1769580684990480384*a(n-23)
%e Some solutions for n=3
%e ..0..0..1..1....0..0..1..1....0..0..1..1....0..1..0..2....0..1..0..0
%e ..1..1..2..2....1..1..0..2....1..1..0..0....0..1..0..2....0..1..2..2
%e ..2..2..1..1....3..3..0..2....2..3..1..1....3..3..2..3....3..3..0..0
%e ..0..0..2..2....0..2..1..1....2..3..0..0....1..1..2..3....0..0..3..3
%e ..3..3..0..0....0..2..3..2....1..2..3..3....2..3..3..2....1..2..1..0
%e ..1..1..3..3....1..1..3..2....1..2..0..0....2..0..0..2....1..2..1..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Oct 23 2011