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A318091 T(n,k)=Number of nXk 0..1 arrays with every element unequal to 0, 2, 3 or 5 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero. 7
1, 1, 1, 1, 2, 1, 1, 2, 2, 1, 1, 3, 2, 3, 1, 1, 5, 7, 7, 5, 1, 1, 10, 7, 47, 7, 10, 1, 1, 23, 11, 159, 159, 11, 23, 1, 1, 54, 15, 547, 493, 547, 15, 54, 1, 1, 131, 62, 1976, 1945, 1945, 1976, 62, 131, 1, 1, 321, 104, 8031, 8525, 10843, 8525, 8031, 104, 321, 1, 1, 789, 141, 32040 (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...2...2.....3......5......10.......23........54........131.........321

.1...2...2.....7......7......11.......15........62........104.........141

.1...3...7....47....159.....547.....1976......8031......32040......126847

.1...5...7...159....493....1945.....8525.....37863.....161424......688404

.1..10..11...547...1945...10843....68301....432496....2725920....16794426

.1..23..15..1976...8525...68301...504606...4057433...31285292...240249513

.1..54..62..8031..37863..432496..4057433..44408035..446314981..4540720013

.1.131.104.32040.161424.2725920.31285292.446314981.5866156032.76596251675

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) = 2*a(n-1) +a(n-2) +a(n-3) -a(n-4) -a(n-5) -a(n-6)

k=3: [order 24]

EXAMPLE

Some solutions for n=5 k=4

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

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

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

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

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

CROSSREFS

Column 2 is A317809.

Sequence in context: A176809 A317815 A318423 * A301608 A285521 A187451

Adjacent sequences:  A318088 A318089 A318090 * A318092 A318093 A318094

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Aug 16 2018

STATUS

approved

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Last modified October 25 13:59 EDT 2021. Contains 348253 sequences. (Running on oeis4.)