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Number of 6Xn 0..5 arrays with no element x(i,j) adjacent to itself or value 5-x(i,j) horizontally, diagonally or antidiagonally, top left element zero, and 1 appearing before 2 3 and 4, and 2 appearing before 3 in row major order (unlabelled 6-colorings with no clashing color pairs)
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%I #4 Dec 05 2013 07:07:35

%S 1248,124928,127533056,82428559360,66799223701504,48667983827959808,

%T 37512454919740719104,28097680435284371570688,

%U 21372669849836167383482368,16126697116955385553150279680,12221294273626033135123316080640

%N Number of 6Xn 0..5 arrays with no element x(i,j) adjacent to itself or value 5-x(i,j) horizontally, diagonally or antidiagonally, top left element zero, and 1 appearing before 2 3 and 4, and 2 appearing before 3 in row major order (unlabelled 6-colorings with no clashing color pairs)

%C Row 6 of A233174

%H R. H. Hardin, <a href="/A233179/b233179.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 448*a(n-1) +421888*a(n-2) -95682560*a(n-3) -48586817536*a(n-4) +7696581394432*a(n-5) +2219020623282176*a(n-6) -331924968239529984*a(n-7) -45544058606667694080*a(n-8) +7676565708838105251840*a(n-9) +384720682715267981115392*a(n-10) -90389119748153097756606464*a(n-11) -732939612340266155036901376*a(n-12) +559176850836005482125888323584*a(n-13) -7028965514623047698676841447424*a(n-14) -1887473560557987165955670813966336*a(n-15) +44169859058027396737075939400220672*a(n-16) +3500683050361467360162023730212503552*a(n-17) -101555160700421718306247628235154128896*a(n-18) -3466958920006006825501354764976208740352*a(n-19) +108207134224866861549607317549181730553856*a(n-20) +1701156622829501613469275506203267231121408*a(n-21) -52659376845749069097884147249280994259238912*a(n-22) -315694924216699133847365011797178367569035264*a(n-23) +9366312983382861719445001674512311832511774720*a(n-24) for n>25

%e Some solutions for n=2

%e ..0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1

%e ..0..2....0..1....5..2....2..1....2..1....2..1....5..1....5..2....2..1....0..1

%e ..5..4....0..2....0..3....2..4....3..1....0..4....5..4....0..2....3..4....0..4

%e ..3..1....0..4....0..4....5..4....0..1....2..4....0..4....5..1....3..5....5..1

%e ..3..0....5..2....5..4....5..1....0..1....3..4....5..2....2..1....1..5....0..4

%e ..4..5....5..3....0..2....3..1....2..4....5..4....5..2....2..5....2..5....2..4

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 05 2013