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A219398
Unchanging value maps: number of n X 3 binary arrays indicating the locations of corresponding elements unequal to no king-move neighbor in a random 0..1 n X 3 array
2
4, 4, 16, 43, 122, 345, 979, 2791, 7936, 22540, 64031, 181974, 517221, 1469927, 4177203, 11870804, 33735384, 95872371, 272457370, 774287065, 2200420843, 6253312335, 17771112208, 50503204860, 143523553079, 407875327102
OFFSET
1,1
COMMENTS
Column 3 of A219403.
LINKS
FORMULA
Empirical: a(n) = 3*a(n-1) - 2*a(n-2) + 3*a(n-3) + 4*a(n-4) + 2*a(n-5) - 5*a(n-6) - 2*a(n-7) for n>8.
Empirical g.f.: x*(4 - 8*x + 12*x^2 - 9*x^3 - 3*x^4 - 7*x^5 + 7*x^6 + 2*x^7) / (1 - 3*x + 2*x^2 - 3*x^3 - 4*x^4 - 2*x^5 + 5*x^6 + 2*x^7). - Colin Barker, Mar 11 2018
EXAMPLE
Some solutions for n=3:
..1..1..1....1..1..1....1..0..0....0..0..0....1..1..1....1..0..0....0..0..1
..0..0..0....1..1..1....1..0..0....0..0..0....1..0..0....0..0..0....0..0..1
..0..0..0....1..1..1....1..1..1....1..1..1....1..0..0....0..0..0....1..1..1
CROSSREFS
Cf. A219403.
Sequence in context: A218051 A092266 A257606 * A222104 A257613 A223202
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 19 2012
STATUS
approved