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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
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
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
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, May 22 2018
STATUS
approved