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A297689 Number of nX3 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 0, 2 or 4 neighboring 1s. 1
5, 26, 95, 415, 1801, 7526, 32173, 137242, 583129, 2484786, 10583683, 45062520, 191933126, 817441956, 3481360348, 14827246426, 63149259874, 268952155501, 1145471423600, 4878575547192, 20777907778014, 88493407078762 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Column 3 of A297694.
LINKS
FORMULA
Empirical: a(n) = 5*a(n-1) -2*a(n-2) +6*a(n-3) -52*a(n-4) +23*a(n-5) -3*a(n-6) +21*a(n-7) -9*a(n-8)
EXAMPLE
Some solutions for n=7
..0..0..0. .1..0..0. .0..0..0. .0..0..1. .0..0..0. .0..0..0. .0..0..1
..0..0..0. .1..0..0. .1..0..1. .0..0..1. .0..0..0. .0..0..1. .0..0..0
..0..0..0. .1..0..0. .0..0..1. .0..0..0. .0..0..1. .0..0..1. .1..1..1
..1..0..0. .0..0..0. .0..0..0. .0..1..1. .0..0..1. .0..0..1. .0..1..0
..0..0..1. .0..0..0. .0..0..1. .1..1..0. .0..0..1. .1..0..0. .1..1..1
..0..0..0. .1..1..1. .0..0..0. .0..0..0. .1..0..1. .1..0..0. .0..0..0
..0..0..0. .1..1..1. .0..1..0. .0..0..0. .1..0..1. .1..0..0. .1..0..1
CROSSREFS
Cf. A297694.
Sequence in context: A350406 A362317 A047669 * A002316 A293799 A211606
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 03 2018
STATUS
approved

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Last modified April 25 01:35 EDT 2024. Contains 371964 sequences. (Running on oeis4.)