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A306124 Number of nX3 0..1 arrays with every element unequal to 0, 1, 3, 4, 6 or 7 king-move adjacent elements, with upper left element zero. 1
3, 7, 9, 19, 39, 73, 147, 319, 681, 1451, 3127, 6789, 14887, 32963, 73569, 165355, 374119, 851749, 1949959, 4486007, 10364533, 24034895, 55913671, 130430861, 304967127, 714466543, 1676614357, 3939963499, 9269602859, 21830156705 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A306129.

LINKS

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

FORMULA

Empirical: a(n) = 3*a(n-1) -a(n-3) -7*a(n-4) +4*a(n-5) -4*a(n-6) -7*a(n-8) +9*a(n-9) +14*a(n-10) +11*a(n-11) -7*a(n-12) -6*a(n-13)

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A306129.

Sequence in context: A224849 A304128 A304539 * A096102 A316157 A045797

Adjacent sequences:  A306121 A306122 A306123 * A306125 A306126 A306127

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jun 22 2018

STATUS

approved

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Last modified February 20 07:38 EST 2020. Contains 332069 sequences. (Running on oeis4.)