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T(n,k)=Petersen graph (3,1) coloring a rectangular array: number of nXk 0..5 arrays where 0..5 label nodes of a graph with edges 0,1 0,3 3,5 3,4 1,2 1,4 4,5 2,0 2,5 and every array movement to a horizontal or antidiagonal neighbor moves along an edge of this graph, with the array starting at 0
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%I #4 Mar 22 2013 05:37:34

%S 1,3,6,9,27,36,27,171,243,216,81,1089,3249,2187,1296,243,6939,44217,

%T 61731,19683,7776,729,44217,609309,1795473,1172889,177147,46656,2187,

%U 281763,8410671,53599905,72906921,22284891,1594323,279936,6561,1795473

%N T(n,k)=Petersen graph (3,1) coloring a rectangular array: number of nXk 0..5 arrays where 0..5 label nodes of a graph with edges 0,1 0,3 3,5 3,4 1,2 1,4 4,5 2,0 2,5 and every array movement to a horizontal or antidiagonal neighbor moves along an edge of this graph, with the array starting at 0

%C Table starts

%C ........1..........3.............9...............27...................81

%C ........6.........27...........171.............1089.................6939

%C .......36........243..........3249............44217...............609309

%C ......216.......2187.........61731..........1795473.............53599905

%C .....1296......19683.......1172889.........72906921...........4715559621

%C .....7776.....177147......22284891.......2960456193.........414863325945

%C ....46656....1594323.....423412929.....120212193177.......36498667573629

%C ...279936...14348907....8044845651....4881332621169.....3211064180380305

%C ..1679616..129140163..152852067369..198211242377097...282501632829717621

%C .10077696.1162261467.2904189280011.8048559615522273.24853807982558115945

%H R. H. Hardin, <a href="/A223556/b223556.txt">Table of n, a(n) for n = 1..219</a>

%F Empirical for column k:

%F k=1: a(n) = 6*a(n-1)

%F k=2: a(n) = 9*a(n-1)

%F k=3: a(n) = 19*a(n-1)

%F k=4: a(n) = 41*a(n-1) -16*a(n-2)

%F k=5: a(n) = 95*a(n-1) -626*a(n-2) +720*a(n-3) for n>4

%F k=6: [order 8] for n>9

%F k=7: [order 13] for n>15

%F Empirical for row n:

%F n=1: a(n) = 3*a(n-1)

%F n=2: a(n) = 7*a(n-1) -4*a(n-2) for n>3

%F n=3: a(n) = 17*a(n-1) -47*a(n-2) +41*a(n-3) -10*a(n-4) for n>6

%F n=4: [order 13] for n>16

%F n=5: [order 41] for n>45

%e Some solutions for n=3 k=4

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

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

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

%Y Column 1 is A000400(n-1)

%Y Column 2 is A013708(n-1)

%Y Column 3 = 9*19^(n-1) is row 8 of A223556 with T(2+,3) = A121057(8,1+)

%Y Row 1 is A000244(n-1)

%K nonn,tabl

%O 1,2

%A _R. H. Hardin_ Mar 22 2013