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A304952 T(n,k)=Number of nXk 0..1 arrays with every element unequal to 0, 2, 3, 5 or 7 king-move adjacent elements, with upper left element zero. 7
1, 1, 1, 1, 4, 1, 1, 7, 7, 1, 1, 13, 13, 13, 1, 1, 26, 21, 21, 26, 1, 1, 49, 29, 26, 29, 49, 1, 1, 99, 58, 70, 70, 58, 99, 1, 1, 194, 120, 139, 189, 139, 120, 194, 1, 1, 387, 250, 287, 468, 468, 287, 250, 387, 1, 1, 773, 515, 625, 1436, 1916, 1436, 625, 515, 773, 1, 1, 1538 (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

.1...4...7...13....26....49.....99.....194......387......773......1538

.1...7..13...21....29....58....120.....250......515.....1100......2302

.1..13..21...26....70...139....287.....625.....1484.....3197......7321

.1..26..29...70...189...468...1436....3753....11101....32272.....92418

.1..49..58..139...468..1916...5296...17450....62128...207139....693887

.1..99.120..287..1436..5296..18950...76117...313593..1223755...4910872

.1.194.250..625..3753.17450..76117..401301..2043622..9772099..49480464

.1.387.515.1484.11101.62128.313593.2043622.12197817.69375211.421959328

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

k=3: [order 18] for n>19

k=4: [order 70] for n>71

EXAMPLE

Some solutions for n=5 k=4

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

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

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

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

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

CROSSREFS

Column 2 is A304004.

Sequence in context: A316733 A304010 A305360 * A316620 A304676 A316123

Adjacent sequences:  A304949 A304950 A304951 * A304953 A304954 A304955

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, May 22 2018

STATUS

approved

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Last modified September 20 05:51 EDT 2019. Contains 327212 sequences. (Running on oeis4.)