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A231246
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T(n,k)=Number of nXk 0..3 arrays x(i,j) with each element horizontally, diagonally or antidiagonally next to at least one element with value (x(i,j)+1) mod 4, no adjacent elements equal, and upper left element zero
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13
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0, 0, 0, 0, 2, 0, 0, 14, 6, 0, 0, 44, 78, 20, 0, 0, 146, 464, 552, 68, 0, 0, 572, 3090, 5992, 3820, 230, 0, 0, 2258, 22460, 76264, 76136, 26658, 778, 0, 0, 8660, 162766, 1081934, 1872136, 968824, 185074, 2632, 0, 0, 33026, 1169472, 15270416, 52280836, 46019438
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OFFSET
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1,5
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COMMENTS
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Table starts
.0....0.......0.........0...........0.............0................0
.0....2......14........44.........146...........572.............2258
.0....6......78.......464........3090.........22460...........162766
.0...20.....552......5992.......76264.......1081934.........15270416
.0...68....3820.....76136.....1872136......52280836.......1450042214
.0..230...26658....968824....46019438....2532190370.....138246711032
.0..778..185074..12322784..1130422470..122516675112...13176773912306
.0.2632.1287036.156753000.27772974680.5929632659798.1256579264497704
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LINKS
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FORMULA
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Empirical for column k:
k=2: a(n) = 3*a(n-1) +a(n-2) +a(n-3)
k=3: a(n) = 4*a(n-1) +16*a(n-2) +26*a(n-3) +37*a(n-4) +6*a(n-5)
k=4: a(n) = 10*a(n-1) +30*a(n-2) +53*a(n-3) +71*a(n-4) -a(n-5) +6*a(n-6) -8*a(n-7)
k=5: [order 19]
k=6: [order 74]
Empirical for row n:
n=2: a(n) = 4*a(n-1) -3*a(n-2) +8*a(n-3) +4*a(n-4) for n>5
n=3: [order 7] for n>8
n=4: [order 22] for n>23
n=5: [order 62] for n>63
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EXAMPLE
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Some solutions for n=2 k=4
..0..3..0..1....0..3..0..3....0..1..0..3....0..1..2..3....0..1..0..1
..2..1..2..3....2..1..0..3....2..3..2..1....0..1..0..1....0..3..2..1
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CROSSREFS
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KEYWORD
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AUTHOR
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STATUS
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approved
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