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A298660
T(n,k)=Number of nXk 0..1 arrays with every element equal to 1, 2, 4, 6 or 7 king-move adjacent elements, with upper left element zero.
6
0, 1, 1, 1, 3, 1, 2, 7, 7, 2, 3, 13, 15, 13, 3, 5, 23, 19, 19, 23, 5, 8, 49, 23, 40, 23, 49, 8, 13, 95, 34, 85, 85, 34, 95, 13, 21, 177, 63, 173, 177, 173, 63, 177, 21, 34, 359, 96, 322, 431, 431, 322, 96, 359, 34, 55, 705, 147, 635, 876, 1116, 876, 635, 147, 705, 55, 89, 1351
OFFSET
1,5
COMMENTS
Table starts
..0...1...1....2....3.....5.....8.....13......21......34.......55........89
..1...3...7...13...23....49....95....177.....359.....705.....1351......2689
..1...7..15...19...23....34....63.....96.....147.....233......368.......588
..2..13..19...40...85...173...322....635....1325....2806.....5877.....12293
..3..23..23...85..177...431...876...2137....5002...11687....27591.....64253
..5..49..34..173..431..1116..2562...6711...17405...48462...125671....334571
..8..95..63..322..876..2562..7964..24801...74358..242072...745571...2349275
.13.177..96..635.2137..6711.24801..89543..322065.1213296..4468276..16453935
.21.359.147.1325.5002.17405.74358.322065.1367704.6098314.26543249.116098205
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = a(n-1) +a(n-2)
k=2: a(n) = 3*a(n-1) -2*a(n-2) +4*a(n-3) -10*a(n-4) +4*a(n-5) for n>6
k=3: [order 18] for n>19
k=4: [order 72] for n>73
EXAMPLE
Some solutions for n=5 k=4
..0..1..1..0. .0..1..1..0. .0..0..1..0. .0..0..1..1. .0..1..0..0
..0..0..0..0. .1..0..0..0. .1..0..1..0. .1..0..1..0. .0..1..0..1
..0..0..0..0. .1..0..0..0. .1..1..1..1. .1..0..0..0. .1..1..1..1
..0..1..0..1. .1..0..1..0. .1..1..1..1. .1..0..0..0. .1..1..1..1
..1..1..0..1. .0..0..1..1. .1..0..0..1. .0..1..1..0. .1..0..0..1
CROSSREFS
Column 1 is A000045(n-1).
Column 2 is A297852.
Column 3 is A298050.
Sequence in context: A298093 A298055 A298888 * A299612 A297959 A298775
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Jan 24 2018
STATUS
approved