A317606 - OEIS

A317606

Number of n X 3 0..1 arrays with every element unequal to 0, 1, 2, 4, 5, 6, 7 or 8 king-move adjacent elements, with upper left element zero.

4, 14, 38, 109, 419, 1413, 4708, 16406, 56424, 192997, 664256, 2285461, 7852493, 26999600, 92853653, 319251681, 1097719967, 3774663142, 12979283717, 44629543176, 153461588223, 527686255393, 1814475510183, 6239176643497

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OFFSET

1,1

COMMENTS

Column 3 of A317611.

LINKS

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

FORMULA

Empirical: a(n) = 2*a(n-1) +5*a(n-2) +13*a(n-3) -22*a(n-4) -72*a(n-5) -88*a(n-6) +97*a(n-7) +314*a(n-8) +287*a(n-9) -138*a(n-10) -472*a(n-11) -290*a(n-12) +41*a(n-13) +93*a(n-14) -9*a(n-15) for n>17.

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A317611.

Sequence in context: A086954 A111583 A124615 * A114845 A141755 A064463

Adjacent sequences: A317603 A317604 A317605 * A317607 A317608 A317609

KEYWORD

nonn

AUTHOR

R. H. Hardin, Aug 01 2018

STATUS

approved