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A283574 Number of 3Xn 0..1 arrays with no 1 equal to more than one of its horizontal, diagonal and antidiagonal neighbors, with the exception of exactly one element. 1
0, 16, 169, 674, 4313, 21186, 104464, 513458, 2431143, 11478378, 53471911, 246887096, 1132514276, 5160569268, 23395062541, 105570183858, 474452680669, 2124725208078, 9484785230640, 42219767106150, 187451695326747 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Row 3 of A283572.
LINKS
FORMULA
Empirical: a(n) = 4*a(n-1) +10*a(n-2) -6*a(n-3) -105*a(n-4) -108*a(n-5) -85*a(n-6) -14*a(n-7) -250*a(n-8) +176*a(n-9) -145*a(n-10) +44*a(n-11) -4*a(n-12)
EXAMPLE
Some solutions for n=4
..1..1..0..1. .0..1..0..0. .0..1..1..0. .0..0..0..0. .1..0..1..0
..1..0..0..0. .0..1..0..0. .1..0..0..0. .0..1..1..0. .1..0..0..1
..0..0..1..0. .1..1..0..1. .1..0..1..0. .0..1..0..1. .1..0..1..0
CROSSREFS
Cf. A283572.
Sequence in context: A205247 A067713 A017210 * A067711 A068175 A238976
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 11 2017
STATUS
approved

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Last modified March 3 09:38 EST 2024. Contains 370499 sequences. (Running on oeis4.)