login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A298454
T(n,k)=Number of nXk 0..1 arrays with every element equal to 1, 3, 4, 5 or 6 king-move adjacent elements, with upper left element zero.
8
0, 1, 1, 0, 4, 0, 1, 4, 4, 1, 0, 16, 0, 16, 0, 1, 48, 11, 11, 48, 1, 0, 88, 26, 161, 26, 88, 0, 1, 240, 46, 478, 478, 46, 240, 1, 0, 704, 204, 2459, 5938, 2459, 204, 704, 0, 1, 1600, 696, 15248, 22133, 22133, 15248, 696, 1600, 1, 0, 4032, 1493, 78163, 206239, 255029
OFFSET
1,5
COMMENTS
Table starts
.0....1....0......1........0.........1...........0.............1
.1....4....4.....16.......48........88.........240...........704
.0....4....0.....11.......26........46.........204...........696
.1...16...11....161......478......2459.......15248.........78163
.0...48...26....478.....5938.....22133......206239.......2539477
.1...88...46...2459....22133....255029.....4095727......62979342
.0..240..204..15248...206239...4095727...112275165....2871621220
.1..704..696..78163..2539477..62979342..2871621220..141892377970
.0.1600.1493.390424.16116493.804773211.62756244756.4903035588074
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = a(n-2)
k=2: a(n) = 2*a(n-1) +8*a(n-3) -8*a(n-4) -8*a(n-5)
k=3: [order 17] for n>18
k=4: [order 53] for n>56
EXAMPLE
Some solutions for n=5 k=4
..0..1..1..1. .0..0..1..1. .0..0..0..0. .0..1..1..0. .0..0..1..1
..1..0..1..1. .1..1..1..1. .1..1..0..0. .0..1..1..0. .0..0..1..1
..0..0..0..1. .1..1..0..0. .1..1..1..1. .0..0..1..1. .1..1..1..1
..0..0..1..1. .1..1..0..0. .0..1..0..0. .0..0..0..1. .0..0..1..1
..1..1..1..1. .1..1..0..0. .0..1..0..0. .0..0..1..0. .0..0..0..0
CROSSREFS
Sequence in context: A298924 A217476 A298622 * A298834 A299588 A299528
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Jan 19 2018
STATUS
approved