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A300682 T(n,k)=Number of nXk 0..1 arrays with every element equal to 0, 2, 3 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero. 7
1, 1, 1, 1, 3, 1, 1, 2, 2, 1, 1, 10, 5, 10, 1, 1, 13, 11, 11, 13, 1, 1, 42, 8, 28, 8, 42, 1, 1, 74, 58, 80, 80, 58, 74, 1, 1, 188, 131, 245, 398, 245, 131, 188, 1, 1, 387, 306, 729, 1382, 1382, 729, 306, 387, 1, 1, 885, 936, 2604, 6686, 9015, 6686, 2604, 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...5...11......8......58......131.......306.........936.........2435

.1..10..11...28.....80.....245......729......2604........8579........27943

.1..13...8...80....398....1382.....6686.....30218......131674.......611429

.1..42..58..245...1382....9015....54361....338173.....2152660.....13818749

.1..74.131..729...6686...54361...494771...4174087....37464671....329141039

.1.188.306.2604..30218..338173..4174087..49274326...607495472...7403455976

.1.387.936.8579.131674.2152660.37464671.607495472.10215309343.174419385580

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..220

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>26

k=4: [order 82] for n>84

EXAMPLE

Some solutions for n=5 k=4

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

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

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

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

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

CROSSREFS

Column 2 is A300374.

Sequence in context: A050169 A143214 A300380 * A300605 A301330 A175636

Adjacent sequences:  A300679 A300680 A300681 * A300683 A300684 A300685

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Mar 11 2018

STATUS

approved

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Last modified February 23 15:24 EST 2020. Contains 332167 sequences. (Running on oeis4.)