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A252507
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Number of (n+2)X(1+2) 0..3 arrays with every 3X3 subblock row and column sum equal to 0 2 5 6 or 7 and every 3X3 diagonal and antidiagonal sum not equal to 0 2 5 6 or 7
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1
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1262, 1515, 2055, 3326, 5508, 9526, 17709, 33357, 62632, 119155, 230081, 444951, 865104, 1681217, 3279686, 6410134, 12571858, 24617069, 48369787, 95007820, 187003788, 367894926, 725427778, 1428661348, 2819873256, 5561285116
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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) = -2*a(n-1) +a(n-2) +21*a(n-3) +44*a(n-4) +3*a(n-5) -167*a(n-6) -398*a(n-7) -244*a(n-8) +541*a(n-9) +1870*a(n-10) +2166*a(n-11) +191*a(n-12) -4546*a(n-13) -8621*a(n-14) -6995*a(n-15) +3369*a(n-16) +17737*a(n-17) +23621*a(n-18) +11388*a(n-19) -16181*a(n-20) -39969*a(n-21) -39148*a(n-22) -8036*a(n-23) +35376*a(n-24) +59826*a(n-25) +44517*a(n-26) -4051*a(n-27) -52799*a(n-28) -66099*a(n-29) -33679*a(n-30) +20761*a(n-31) +57309*a(n-32) +52424*a(n-33) +12871*a(n-34) -29613*a(n-35) -46287*a(n-36) -29416*a(n-37) +3586*a(n-38) +27436*a(n-39) +28338*a(n-40) +10553*a(n-41) -9495*a(n-42) -18317*a(n-43) -12920*a(n-44) -1337*a(n-45) +7278*a(n-46) +8319*a(n-47) +4329*a(n-48) -406*a(n-49) -2641*a(n-50) -2423*a(n-51) -1106*a(n-52) -10*a(n-53) +426*a(n-54) +428*a(n-55) +210*a(n-56) +57*a(n-57) -29*a(n-58) -36*a(n-59) -18*a(n-60) -6*a(n-61) for n>68
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EXAMPLE
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Some solutions for n=4
..3..2..1....2..1..3....2..3..2....0..2..3....1..1..0....1..3..1....3..2..0
..2..2..1....1..3..1....2..3..1....1..0..1....3..0..2....2..1..3....2..1..2
..1..1..3....3..1..3....3..1..3....1..0..1....1..1..0....2..3..1....0..2..0
..2..2..1....1..3..1....1..3..1....3..0..3....1..1..0....2..1..3....0..2..0
..3..2..1....2..1..3....2..1..3....2..0..3....3..0..2....1..3..1....2..3..2
..1..1..0....2..3..1....2..3..2....1..0..1....3..1..3....2..2..3....0..2..0
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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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