login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A231523 T(n,k)=Number of nXk 0..1 arrays with no element less than a strict majority of its horizontal, diagonal and antidiagonal neighbors 13
2, 2, 4, 4, 10, 8, 7, 34, 21, 16, 12, 107, 153, 48, 32, 21, 342, 865, 776, 113, 64, 37, 1069, 4665, 7697, 3861, 261, 128, 65, 3381, 25556, 70462, 66499, 18721, 601, 256, 114, 10689, 144847, 680302, 1031105, 571226, 91993, 1390, 512, 200, 33808, 817539 (list; table; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Table starts
....2....2........4..........7...........12..............21................37
....4...10.......34........107..........342............1069..............3381
....8...21......153........865.........4665...........25556............144847
...16...48......776.......7697........70462..........680302...........6935963
...32..113.....3861......66499......1031105........17572772.........322599407
...64..261....18721.....571226.....15000701.......451200772.......14940780666
..128..601....91993....4944075....219937967.....11683058939......697702378939
..256.1390...453274...42759650...3222629836....302190345444....32529760276112
..512.3216..2223662..369356733..47159743290...7806399525348..1514885617016157
.1024.7435.10915727.3191749214.690399979855.201765495180944.70592106166184098
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = 2*a(n-1)
k=2: a(n) = 3*a(n-1) -2*a(n-2) +2*a(n-3) -2*a(n-4) -a(n-5) for n>6
k=3: [order 13] for n>14
k=4: [order 24] for n>25
k=5: [order 70] for n>71
Empirical for row n:
n=1: a(n) = 2*a(n-1) -a(n-2) +a(n-3) for n>4
n=2: a(n) = 4*a(n-1) -3*a(n-2) +a(n-3) +6*a(n-4) -18*a(n-5)
n=3: [order 16] for n>17
n=4: [order 39] for n>40
EXAMPLE
Some solutions for n=4 k=4
..1..0..0..0....1..0..1..1....1..1..0..1....0..0..0..0....0..1..0..1
..1..0..0..0....0..0..0..1....1..0..0..0....0..0..0..1....1..0..0..0
..0..0..0..0....0..0..1..0....0..0..0..1....1..0..0..1....1..0..1..0
..0..1..1..1....0..0..0..0....0..1..0..0....0..0..0..1....0..0..0..1
CROSSREFS
Column 1 is A000079
Column 2 is A231376
Row 1 is A005251(n+2)
Sequence in context: A109525 A243330 A318838 * A114338 A170831 A133406
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Nov 10 2013
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified June 23 21:26 EDT 2024. Contains 373654 sequences. (Running on oeis4.)