A211598 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, seven or eight distinct values for every i,j,k<=n

16, 48, 128, 322, 780, 1874, 4400, 10458, 24332, 57922, 134744, 322650, 753100, 1815874, 4256984, 10332338, 24326116, 59383402, 140337800, 344230370, 816065860, 2009539410, 4776207920, 11798294714, 28099290420, 69585826082

Offset

1,1

Links

R. H. Hardin, Table of n, a(n) for n = 1..55

Formula

Empirical: a(n) = 2*a(n-1) +16*a(n-2) -31*a(n-3) -97*a(n-4) +178*a(n-5) +284*a(n-6) -473*a(n-7) -418*a(n-8) +578*a(n-9) +288*a(n-10) -270*a(n-11) -72*a(n-12) +36*a(n-13)

Example

Some solutions for n=5
..1....2...-1....0....1...-2....1....2....0....0....0...-1...-1....1...-2....1
..0....0....0...-1...-2...-1....2....1...-1...-2....1....0....0....0...-1....0
.-1....2...-1...-2...-1....0...-1....0....2...-1....0....1...-1....2....0....2
..0...-1....0....0...-2...-1...-2....1....1...-2...-1....2...-2....1...-1....1
..1....2...-1...-1...-1....0...-1....2....2....1...-2....1....1....2...-2....2
..0...-1....0....0....0....1...-2....1....1...-2...-1....2....2...-1...-1....0

Crossrefs

Sequence in context: A211576 A211590 A211584 * A235541 A109098 A223395

Adjacent sequences: A211595 A211596 A211597 * A211599 A211600 A211601

Keyword

nonn

Author

R. H. Hardin Apr 16 2012

Status

approved