login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo

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 56th year, we are closing in on 350,000 sequences, and we’ve crossed 9,700 citations (which often say “discovered thanks to the OEIS”).

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A186568 T(n,k)=Number of (n+2)X(k+2) 0..2 arrays with every 3X3 subblock commuting with each horizontal and vertical neighbor 3X3 subblock 10
19683, 721, 721, 2917, 173, 2917, 6594, 401, 401, 6594, 12122, 1411, 1399, 1411, 12122, 20056, 2617, 3421, 3421, 2617, 20056, 29303, 3379, 4807, 8983, 4807, 3379, 29303, 35198, 4033, 5605, 11557, 11557, 5605, 4033, 35198, 53611, 4795, 6511, 12895 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Table starts

.19683...721..2917..6594.12122.20056..29303..35198..53611..85029.121783.199305

...721...173...401..1411..2617..3379...4033...4795...6361..10443..17153..26995

..2917...401..1399..3421..4807..5605...6511...8029..11647..19237..31623..49805

..6594..1411..3421..8983.11557.12895..14845..18415..25381..40279..63565.102591

.12122..2617..4807.11557.21007.23389..27391..33445..44263..68269.104335.154693

.20056..3379..5605.12895.23389.29935..36133..44887..60493..91519.137701.205879

.29303..4033..6511.14845.27391.36133..47719..60973..82447.122725.185863.278125

.35198..4795..8029.18415.33445.44887..60973..82783.112357.168727.255085.381007

.53611..6361.11647.25381.44263.60493..82447.112357.168391.250285.374335.562933

.85029.10443.19237.40279.68269.91519.122725.168727.250285.441199.644917.946087

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..1404

FORMULA

Empirical, for all columns: a(n)=2*a(n-1)-a(n-2)+2*a(n-3)-4*a(n-4)+2*a(n-5)+2*a(n-6)-2*a(n-7) for n>18,10,11,12,13,14,15,16 respectively for k=1..8

EXAMPLE

Some solutions for 5X4

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

..2..0..0..1....0..0..0..0....0..0..0..1....0..0..0..0....0..0..0..0

..0..2..0..0....0..0..0..0....0..0..0..1....1..0..0..0....0..0..0..0

..0..0..2..0....1..0..0..0....0..0..0..1....2..1..0..0....0..0..0..0

..0..0..0..2....0..0..0..2....0..0..0..1....1..2..1..0....0..1..0..0

CROSSREFS

Sequence in context: A206133 A321825 A186559 * A186560 A046322 A224658

Adjacent sequences:  A186565 A186566 A186567 * A186569 A186570 A186571

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin Feb 23 2011

STATUS

approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified December 3 15:58 EST 2021. Contains 349467 sequences. (Running on oeis4.)