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A211590 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 four, five, six or eight distinct values for every i,j,k<=n 1
16, 48, 124, 306, 712, 1682, 3824, 9010, 20556, 48942, 112920, 272310, 635488, 1549486, 3649084, 8971242, 21265496, 52582858, 125191648, 310754154, 741987532, 1846432766, 4416892952, 11009384758, 26366956992, 65790531678, 157684077564 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = 4*a(n-1) +11*a(n-2) -61*a(n-3) -20*a(n-4) +343*a(n-5) -156*a(n-6) -890*a(n-7) +756*a(n-8) +1066*a(n-9) -1196*a(n-10) -504*a(n-11) +720*a(n-12) +72*a(n-13) -144*a(n-14)
EXAMPLE
Some solutions for n=5
.-1...-1...-1....2...-2...-1....1....2...-1....1...-1...-1....1...-2...-1....1
..0...-2...-2...-1...-1...-2....0....1...-2...-2....0...-2....2....0....2....2
.-1...-1....0...-2...-2....1...-1....0....0...-1...-1....1...-1...-1...-1....1
..0....0....2...-1....1....0....0....2...-2...-2....0....2....2....0....2....0
..1...-2....0...-2...-2...-1....1....0...-1...-1...-1...-1....1...-1....0...-1
..0....0....2...-1....0....2....2....1...-2....0....0....2....0...-2....2...-2
CROSSREFS
Sequence in context: A331772 A190112 A211576 * A211584 A211598 A235541
KEYWORD
nonn
AUTHOR
R. H. Hardin Apr 16 2012
STATUS
approved

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Last modified April 19 12:14 EDT 2024. Contains 371792 sequences. (Running on oeis4.)