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A274730
Number of 5 X n 0..2 arrays with no element equal to any value at offset (-1,-2) (-2,-1) or (-1,0) and new values introduced in order 0..2.
1
8, 144, 1040, 9308, 84948, 771300, 7016284, 63780144, 579907180, 5272264616, 47934377596, 435805897172, 3962236677384, 36023613993928, 327517339347916, 2977702208511048, 27072492754395896, 246136048094770872
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = 10*a(n-1) - a(n-2) - 80*a(n-3) + 133*a(n-4) - 49*a(n-5) - 16*a(n-6) + 4*a(n-7) for n>9.
Empirical g.f.: 4*x*(2 + 16*x - 98*x^2 - 77*x^3 + 841*x^4 - 1108*x^5 + 434*x^6 - 72*x^7 + 24*x^8) / ((1 - x)*(1 - 9*x - 8*x^2 + 72*x^3 - 61*x^4 - 12*x^5 + 4*x^6)). - Colin Barker, Jan 30 2019
EXAMPLE
Some solutions for n=4:
..0..1..0..0. .0..1..0..2. .0..1..2..1. .0..1..0..2. .0..1..2..2
..2..0..1..2. .1..0..1..0. .1..0..1..2. .1..0..1..0. .1..0..1..0
..1..1..0..1. .2..1..2..1. .2..1..2..1. .0..2..0..1. .0..1..0..1
..2..0..2..0. .1..0..1..0. .0..0..1..2. .1..0..2..0. .2..0..1..0
..1..2..0..2. .2..1..0..1. .2..1..2..1. .2..2..0..1. .0..2..0..2
CROSSREFS
Row 5 of A274728.
Sequence in context: A275139 A370071 A241229 * A263604 A212703 A065409
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jul 03 2016
STATUS
approved