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A300380 T(n,k)=Number of nXk 0..1 arrays with every element equal to 0, 2 or 3 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero. 8
1, 1, 1, 1, 3, 1, 1, 2, 2, 1, 1, 10, 4, 10, 1, 1, 13, 11, 11, 13, 1, 1, 42, 8, 26, 8, 42, 1, 1, 74, 58, 80, 80, 58, 74, 1, 1, 188, 131, 237, 389, 237, 131, 188, 1, 1, 387, 306, 692, 1351, 1351, 692, 306, 387, 1, 1, 885, 936, 2548, 6577, 8839, 6577, 2548, 936, 885, 1, 1, 1937 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,5

COMMENTS

Table starts

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

.1...3...2...10.....13......42.......74.......188........387..........885

.1...2...4...11......8......58......131.......306........936.........2435

.1..10..11...26.....80.....237......692......2548.......8240........26808

.1..13...8...80....389....1351.....6577.....29663.....128834.......599170

.1..42..58..237...1351....8839....53367....330577....2105279.....13511213

.1..74.131..692...6577...53367...481311...4070089...36505624....319929622

.1.188.306.2548..29663..330577..4070089..47968011..590197943...7181318177

.1.387.936.8240.128834.2105279.36505624.590197943.9905247305.168928472097

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..238

FORMULA

Empirical for column k:

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

k=2: a(n) = 4*a(n-2) +2*a(n-3) +a(n-5) -3*a(n-6) +a(n-7)

k=3: [order 23] for n>25

k=4: [order 80] for n>82

EXAMPLE

Some solutions for n=5 k=4

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

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

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

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

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

CROSSREFS

Sequence in context: A073166 A050169 A143214 * A300682 A300605 A301330

Adjacent sequences:  A300377 A300378 A300379 * A300381 A300382 A300383

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Mar 04 2018

STATUS

approved

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Last modified April 6 05:38 EDT 2020. Contains 333267 sequences. (Running on oeis4.)