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A255023
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Number of (n+2)X(4+2) 0..1 arrays with no 3x3 subblock diagonal sum 0 or 1 and no antidiagonal sum 0 or 1 and no row sum 0 or 1 and no column sum 0 or 1
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1
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269, 1121, 5077, 21854, 92217, 391926, 1669286, 7114859, 30309034, 129016023, 549319029, 2339546992, 9963141837, 42425232242, 180661430018, 769335984165, 3276146397830, 13951092432171, 59409215103985, 252988054381890
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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) = a(n-1) +6*a(n-2) +20*a(n-3) +54*a(n-4) +38*a(n-5) -41*a(n-6) -191*a(n-7) -285*a(n-8) +296*a(n-9) +753*a(n-10) -160*a(n-11) -791*a(n-12) -99*a(n-13) +334*a(n-14) +98*a(n-15) -18*a(n-16) +54*a(n-17) -3*a(n-18) -35*a(n-19) +3*a(n-20) -12*a(n-21) -7*a(n-22) +4*a(n-23) for n>25
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EXAMPLE
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Some solutions for n=4
..1..1..1..0..1..1....0..1..1..1..0..1....1..0..1..1..1..1....1..0..1..1..1..1
..1..0..1..1..1..0....1..1..0..1..1..1....1..1..1..1..1..0....1..1..1..0..1..1
..1..1..1..1..1..1....1..1..1..1..1..0....1..1..0..1..1..1....1..1..1..1..1..1
..1..1..1..1..1..1....1..1..1..1..1..1....0..1..1..1..1..1....1..1..1..1..1..1
..0..1..1..1..1..0....0..1..1..1..1..1....1..1..1..1..1..1....1..1..1..1..1..0
..1..1..1..0..1..1....1..1..0..1..1..0....1..1..1..1..0..1....0..1..1..0..1..1
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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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