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A211579
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Number of -2..2 arrays x(i) of n+1 elements i=1..n+1 with set{t,u,v in 0,1}((x[i+t]+x[j+u]+x[k+v])*(-1)^(t+u+v)) having one, three, four, five or six distinct values for every i,j,k<=n
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1
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17, 61, 185, 505, 1301, 3279, 8057, 19877, 48327, 119027, 289945, 717461, 1757523, 4374935, 10781761, 26985609, 66861615, 168098793, 418354859, 1055489197, 2636379211, 6669352191, 16707630313, 42352772917, 106355179479, 270028712725
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OFFSET
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1,1
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LINKS
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FORMULA
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Empirical: a(n) = 7*a(n-1) +5*a(n-2) -135*a(n-3) +146*a(n-4) +1064*a(n-5) -1994*a(n-6) -4450*a(n-7) +11503*a(n-8) +10456*a(n-9) -38079*a(n-10) -12441*a(n-11) +78724*a(n-12) +1556*a(n-13) -103670*a(n-14) +15762*a(n-15) +85188*a(n-16) -20943*a(n-17) -40966*a(n-18) +11896*a(n-19) +10080*a(n-20) -3060*a(n-21) -936*a(n-22) +288*a(n-23)
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EXAMPLE
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Some solutions for n=5
..0...-2....0....0...-1....1....1....2....0....0....2...-1....1....1....1....2
..0...-1....0....1....0....0....0....0....0....0....0....0...-2....0....0....0
..0...-2...-2....0...-1...-2...-1...-2....0....2....1....1....1....2....2...-2
..0...-1....0...-2....0...-1....0...-1....2....0....0....2...-2....1....1....0
..1....2....0....0....0....0....0...-2....0...-1...-1...-1...-1....0....2...-2
..2....0....2...-1....1....1....1....0....2...-2....0...-2....0....2....1....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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