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A299592
Number of n X 5 0..1 arrays with every element unequal to 0, 1 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
1
8, 8, 19, 53, 113, 256, 541, 1148, 2488, 5349, 11453, 24617, 52916, 113605, 243988, 524156, 1125805, 2417997, 5193737, 11155712, 23961101, 51466060, 110544232, 237437573, 509991637, 1095411153, 2352832580, 5053645925, 10854721796
OFFSET
1,1
COMMENTS
Column 5 of A299595.
LINKS
FORMULA
Empirical: a(n) = a(n-1) +a(n-2) +3*a(n-3) +a(n-4) -a(n-5) -a(n-6) for n>9.
Empirical g.f.: x*(8 + 3*x^2 + 2*x^3 + 9*x^4 + 33*x^5 + 10*x^6 - 14*x^7 - 10*x^8) / ((1 + x^2 - x^3)*(1 - x - 2*x^2 - x^3)). - Colin Barker, Feb 15 2018
EXAMPLE
Some solutions for n=5:
..0..0..1..0..0. .0..0..0..0..0. .0..0..0..0..0. .0..0..1..0..0
..0..0..0..0..0. .0..0..0..0..0. .1..0..0..0..0. .0..0..0..0..1
..0..0..0..0..0. .1..0..0..0..1. .0..0..0..0..0. .0..0..0..0..0
..0..0..0..0..0. .0..0..0..0..0. .0..0..0..0..0. .1..0..0..0..0
..0..0..1..0..0. .0..1..0..0..0. .0..1..0..0..0. .0..0..0..1..0
CROSSREFS
Cf. A299595.
Sequence in context: A298166 A298956 A232652 * A339707 A061156 A359037
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 13 2018
STATUS
approved