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A275404
Number of 5 X n 0..2 arrays with no element equal to any value at offset (-2,-1) (-2,0) or (-1,1) and new values introduced in order 0..2.
1
12, 63, 394, 2404, 14884, 91849, 566331, 3495079, 21564220, 133044851, 820883765, 5064781430, 31249159768, 192804508189, 1189585924729, 7339632833601, 45284849272769, 279403286034674, 1723892118671285, 10636253097506243
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) + 15*a(n-2) + 55*a(n-3) + 69*a(n-4) + 8*a(n-5) - 50*a(n-6) + 14*a(n-7) + a(n-8) - a(n-9) for n>10.
Empirical g.f.: x*(12 + 39*x + 88*x^2 + 11*x^3 - 127*x^4 - 92*x^5 + 63*x^6 + 16*x^7 - 20*x^8 + x^9) / (1 - 2*x - 15*x^2 - 55*x^3 - 69*x^4 - 8*x^5 + 50*x^6 - 14*x^7 - x^8 + x^9). - Colin Barker, Feb 04 2019
EXAMPLE
Some solutions for n=4:
..0..1..2..2. .0..1..1..1. .0..0..1..2. .0..1..1..1. .0..0..1..2
..2..0..1..2. .0..0..0..1. .2..2..0..1. .2..0..0..0. .2..0..0..0
..1..2..0..0. .1..2..0..0. .1..1..2..0. .2..2..2..2. .2..2..2..0
..1..1..2..0. .1..2..1..2. .0..1..1..2. .0..1..1..2. .0..1..2..1
..0..0..1..2. .0..0..1..2. .2..2..0..1. .0..0..1..1. .0..0..0..1
CROSSREFS
Row 5 of A275401.
Sequence in context: A051922 A027810 A012875 * A162472 A008425 A154507
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jul 26 2016
STATUS
approved