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A306131 Number of nX3 0..1 arrays with every element unequal to 0, 2, 3, 4, 6 or 7 king-move adjacent elements, with upper left element zero. 2
1, 8, 13, 64, 240, 842, 3302, 12740, 48468, 187112, 723138, 2786916, 10760740, 41576054, 160572130, 620281406, 2396512260, 9258772148, 35771455196, 138208433662, 533989093282, 2063152495586, 7971370390066, 30798897460570 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 3 of A306136.

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..210

FORMULA

Empirical: a(n) = 5*a(n-1) -3*a(n-2) +2*a(n-3) -29*a(n-4) -18*a(n-5) +80*a(n-6) -17*a(n-7) +7*a(n-8) +102*a(n-9) -112*a(n-10) -65*a(n-11) +61*a(n-12) -71*a(n-13) +49*a(n-14) +68*a(n-15) -72*a(n-16) -14*a(n-17) -16*a(n-19) -4*a(n-20)

EXAMPLE

Some solutions for n=5

..0..0..0. .0..1..0. .0..1..0. .0..1..0. .0..1..0. .0..1..1. .0..1..0

..1..1..1. .0..1..0. .0..1..1. .1..0..1. .0..1..0. .0..1..1. .1..1..1

..0..0..0. .1..1..1. .0..0..0. .0..0..0. .1..1..1. .1..0..0. .0..0..1

..0..0..1. .0..0..1. .0..1..0. .0..1..0. .0..1..0. .1..0..0. .1..1..0

..1..1..0. .1..0..1. .1..0..1. .1..0..1. .1..0..1. .0..1..1. .1..1..0

CROSSREFS

Cf. A306136.

Sequence in context: A304546 A166670 A107764 * A177183 A228799 A220393

Adjacent sequences:  A306128 A306129 A306130 * A306132 A306133 A306134

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jun 22 2018

STATUS

approved

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Last modified October 22 10:20 EDT 2019. Contains 328317 sequences. (Running on oeis4.)