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A301349
Number of nX3 0..1 arrays with every element equal to 1, 2, 3, 5 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
1
1, 10, 53, 277, 1433, 7522, 39390, 206370, 1081141, 5664201, 29675091, 155470142, 814520042, 4267334800, 22356902816, 117129577486, 613651093697, 3214966486924, 16843463025482, 88244231458054, 462318489581630
OFFSET
1,2
COMMENTS
Column 3 of A301354.
LINKS
FORMULA
Empirical: a(n) = 5*a(n-1) +5*a(n-2) -19*a(n-3) -6*a(n-4) +14*a(n-5) -3*a(n-6) +16*a(n-7) +19*a(n-8) -59*a(n-9) -41*a(n-10) +29*a(n-11) +8*a(n-12) +24*a(n-13) +51*a(n-14) -6*a(n-15) -32*a(n-16) -4*a(n-17) +4*a(n-18) for n>20
EXAMPLE
Some solutions for n=5
..0..0..0. .0..1..1. .0..0..0. .0..1..0. .0..0..0. .0..0..1. .0..0..0
..0..1..0. .0..0..1. .0..1..0. .0..1..0. .0..1..0. .0..1..1. .0..1..1
..1..1..0. .0..1..0. .1..0..0. .0..1..0. .1..0..1. .1..0..0. .0..0..1
..0..1..0. .1..0..1. .1..1..1. .0..1..0. .1..0..1. .1..0..1. .1..1..1
..0..1..1. .1..1..1. .1..0..0. .1..1..0. .1..1..1. .1..1..1. .0..0..0
CROSSREFS
Cf. A301354.
Sequence in context: A300422 A300684 A300607 * A007035 A093187 A208616
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 19 2018
STATUS
approved