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A204642
T(n,k)=Number of (n+2)X(k+2) 0..3 arrays with every 3X3 subblock having three equal elements in a row horizontally, vertically, diagonally or antidiagonally exactly three ways, and new values 0..3 introduced in row major order
9
124, 405, 405, 1781, 1884, 1781, 4246, 5974, 5974, 4246, 16855, 379, 248, 379, 16855, 65096, 1860, 933, 933, 1860, 65096, 144255, 2239, 760, 478, 760, 2239, 144255, 651750, 8140, 2517, 1169, 1169, 2517, 8140, 651750, 2480147, 32206, 9750, 4366
OFFSET
1,1
COMMENTS
Table starts
....124...405..1781..4246.16855.65096.144255.651750.2480147.6826114.28519709
....405..1884..5974...379..1860..2239...8140..32206..107738..407469..1548886
...1781..5974...248...933...760..2517...9750..28856..108520..412247..1538786
...4246...379...933...478..1169..4366...8179..29877..113861..407328..1541643
..16855..1860...760..1169..3300..3077...9482..35500..109224..410467..1557742
..65096..2239..2517..4366..3077..5446..16171..31929..113429..427632..1544127
.144255..8140..9750..8179..9482.16171..16636..40170..134630..418053..1557876
.651750.32206.28856.29877.35500.31929..40170..76664..140344..447095..1625798
LINKS
FORMULA
Empirical for column k:
k=1: (order 28 recurrence for n>29)
k=2: a(n) = 4*a(n-1) +a(n-2) -2*a(n-3) -19*a(n-4) -4*a(n-5) +21*a(n-6) +24*a(n-7) +3*a(n-8) -18*a(n-9) -9*a(n-10) for n>13
k=3: a(n) = 5*a(n-1) -3*a(n-2) -4*a(n-3) -12*a(n-4) +12*a(n-5) +21*a(n-6) -9*a(n-7) -9*a(n-8) for n>10
k=4: a(n) = 5*a(n-1) -3*a(n-2) -4*a(n-3) -12*a(n-4) +12*a(n-5) +21*a(n-6) -9*a(n-7) -9*a(n-8) for n>10
k=5: a(n) = 5*a(n-1) -3*a(n-2) -4*a(n-3) -12*a(n-4) +12*a(n-5) +21*a(n-6) -9*a(n-7) -9*a(n-8) for n>10
k=6: a(n) = 5*a(n-1) -3*a(n-2) -4*a(n-3) -12*a(n-4) +12*a(n-5) +21*a(n-6) -9*a(n-7) -9*a(n-8) for n>10
k=7: a(n) = 5*a(n-1) -3*a(n-2) -4*a(n-3) -12*a(n-4) +12*a(n-5) +21*a(n-6) -9*a(n-7) -9*a(n-8) for n>10
EXAMPLE
Some solutions for n=3 k=3
..0..0..1..1..0....0..0..0..0..0....0..0..0..0..0....0..0..0..0..0
..0..0..1..1..0....0..0..0..0..0....0..0..0..0..0....0..0..0..0..0
..0..0..1..1..0....1..1..1..1..1....1..1..1..1..1....1..1..1..1..1
..0..0..1..1..0....0..0..0..0..0....1..1..1..1..1....1..1..1..1..1
..0..0..1..1..0....1..1..1..1..1....0..0..0..0..0....0..0..0..0..0
CROSSREFS
Sequence in context: A214485 A045250 A258931 * A204635 A102589 A189812
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin Jan 17 2012
STATUS
approved