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A296405 T(n,k)=Number of nXk 0..1 arrays with each 1 horizontally, vertically or antidiagonally adjacent to 2 or 3 neighboring 1s. 8
1, 1, 1, 1, 4, 1, 1, 8, 8, 1, 1, 17, 24, 17, 1, 1, 46, 82, 82, 46, 1, 1, 114, 316, 444, 316, 114, 1, 1, 289, 1182, 2868, 2868, 1182, 289, 1, 1, 757, 4560, 17783, 35561, 17783, 4560, 757, 1, 1, 1964, 17508, 110554, 368770, 368770, 110554, 17508, 1964, 1, 1, 5118, 67310 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,5

COMMENTS

Table starts

.1....1.....1.......1.........1...........1.............1...............1

.1....4.....8......17........46.........114...........289.............757

.1....8....24......82.......316........1182..........4560...........17508

.1...17....82.....444......2868.......17783........110554..........688248

.1...46...316....2868.....35561......368770.......3939121........42629909

.1..114..1182...17783....368770.....6200926.....107541673......1896487480

.1..289..4560..110554...3939121...107541673....3068113721.....90097748288

.1..757.17508..688248..42629909..1896487480...90097748288...4427644444522

.1.1964.67310.4288144.457078213.33169242951.2600708602697.211857339895816

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..263

FORMULA

Empirical for column k:

k=1: a(n) = a(n-1)

k=2: [order 9]

k=3: [order 20]

k=4: [order 52]

EXAMPLE

Some solutions for n=5 k=4

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

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

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

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

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

CROSSREFS

Sequence in context: A132789 A319251 A100754 * A174035 A303888 A305281

Adjacent sequences:  A296402 A296403 A296404 * A296406 A296407 A296408

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Dec 11 2017

STATUS

approved

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Last modified October 15 15:14 EDT 2019. Contains 328030 sequences. (Running on oeis4.)