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A240396
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Number of 4Xn 0..3 arrays with no element equal to zero plus the sum of elements to its left or one plus the sum of the elements above it or two plus the sum of the elements diagonally to its northwest, modulo 4
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1
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4, 50, 258, 954, 3064, 9075, 27120, 73312, 187700, 454607, 1054023, 2348091, 5040527, 10456925, 21019462, 41033776, 77965751, 144468320, 261540590, 463367238, 804614463, 1371267840, 2296511220, 3783694051, 6139153725
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OFFSET
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1,1
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COMMENTS
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LINKS
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FORMULA
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Empirical: a(n) = (1/8717829120)*n^14 - (17/2075673600)*n^13 + (83/159667200)*n^12 - (317/17740800)*n^11 + (22217/43545600)*n^10 - (161857/14515200)*n^9 + (67319279/304819200)*n^8 - (7456547/2073600)*n^7 + (100092067/2419200)*n^6 - (27432253/134400)*n^5 - (16160141119/7484400)*n^4 + (244256373721/4989600)*n^3 - (60250176112681/151351200)*n^2 + (111761986901/72072)*n - 2304050 for n>13
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EXAMPLE
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Some solutions for n=4
..3..0..0..0....3..0..0..0....3..0..0..0....3..0..0..0....3..0..0..0
..3..0..0..0....1..0..0..3....3..2..0..3....1..0..0..3....1..3..3..0
..1..2..2..3....3..2..0..3....1..0..2..1....3..2..2..1....3..1..3..2
..1..2..0..2....3..2..0..2....3..0..0..2....1..0..0..0....3..2..2..2
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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