A297689 - OEIS

A297689

Number of nX3 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 0, 2 or 4 neighboring 1s.

5, 26, 95, 415, 1801, 7526, 32173, 137242, 583129, 2484786, 10583683, 45062520, 191933126, 817441956, 3481360348, 14827246426, 63149259874, 268952155501, 1145471423600, 4878575547192, 20777907778014, 88493407078762

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

Column 3 of A297694.

LINKS

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

FORMULA

Empirical: a(n) = 5*a(n-1) -2*a(n-2) +6*a(n-3) -52*a(n-4) +23*a(n-5) -3*a(n-6) +21*a(n-7) -9*a(n-8)

EXAMPLE

Some solutions for n=7

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

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

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

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

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

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

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

CROSSREFS

Cf. A297694.

Sequence in context: A350406 A362317 A047669 * A002316 A293799 A211606

Adjacent sequences: A297686 A297687 A297688 * A297690 A297691 A297692

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 03 2018

STATUS

approved