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A304692 Number of nX3 0..1 arrays with every element unequal to 1, 2, 3, 5 or 6 king-move adjacent elements, with upper left element zero. 1
1, 16, 56, 178, 669, 2615, 9573, 35581, 133149, 495719, 1845526, 6880247, 25634622, 95503501, 355868278, 1325975629, 4940513437, 18408548266, 68590644744, 255569164599, 952255335447, 3548119872982, 13220347086909, 49259228193957 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 3 of A304697.

LINKS

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

FORMULA

Empirical: a(n) = 3*a(n-1) +4*a(n-2) +7*a(n-3) -28*a(n-4) -63*a(n-5) -22*a(n-6) +66*a(n-7) +200*a(n-8) +120*a(n-9) -46*a(n-10) -245*a(n-11) -185*a(n-12) -23*a(n-13) +95*a(n-14) +162*a(n-15) +71*a(n-16) -2*a(n-17) -20*a(n-18) -8*a(n-19) for n>21

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A304697.

Sequence in context: A331766 A231971 A333279 * A295986 A169882 A202993

Adjacent sequences:  A304689 A304690 A304691 * A304693 A304694 A304695

KEYWORD

nonn

AUTHOR

R. H. Hardin, May 17 2018

STATUS

approved

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Last modified June 15 04:47 EDT 2021. Contains 345043 sequences. (Running on oeis4.)