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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A204381 T(n,k)=Number of (n+2)X(k+2) 0..1 arrays with every 3X3 subblock having three equal elements in a row horizontally, vertically or nw-to-se diagonally exactly three ways, and new values 0..1 introduced in row major order 9
33, 51, 51, 78, 48, 78, 113, 54, 54, 113, 182, 63, 61, 63, 182, 286, 88, 75, 75, 88, 286, 439, 128, 98, 87, 98, 128, 439, 710, 193, 139, 111, 111, 139, 193, 710, 1128, 300, 205, 153, 136, 153, 205, 300, 1128, 1775, 470, 310, 217, 176, 176, 217, 310, 470, 1775, 2873 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Table starts

..33..51..78.113.182.286.439.710.1128.1775.2873.4628.7422.12063.19589.31772

..51..48..54..63..88.128.193.300..470..747.1196.1920.3093..4992..8062.13031

..78..54..61..75..98.139.205.310..481..759.1206.1931.3105..5002..8073.13043

.113..63..75..87.111.153.217.323..495..771.1219.1945.3117..5015..8087.13055

.182..88..98.111.136.176.241.348..518..795.1244.1968.3141..5040..8110.13079

.286.128.139.153.176.217.283.388..559..837.1284.2009.3183..5080..8151.13121

.439.193.205.217.241.283.347.453..625..901.1349.2075.3247..5145..8217.13185

.710.300.310.323.348.388.453.560..730.1007.1456.2180.3353..5252..8322.13291

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..1103

FORMULA

Empirical for column k:

k=1: a(n)=3*a(n-1)-2*a(n-2)-2*a(n-4)+2*a(n-5)+3*a(n-6)-6*a(n-7)+3*a(n-8)-a(n-11)+2*a(n-12)-a(n-13)-a(n-14)+2*a(n-15)-a(n-16)

k=2..7: a(n) = a(n-1) +a(n-2) +a(n-3) -a(n-4) -a(n-5) for n>8

EXAMPLE

Some solutions for n=3 k=3

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

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

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

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

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

CROSSREFS

Sequence in context: A020293 A226698 A096278 * A034815 A014976 A109407

Adjacent sequences:  A204378 A204379 A204380 * A204382 A204383 A204384

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin Jan 14 2012

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 July 27 23:16 EDT 2021. Contains 346316 sequences. (Running on oeis4.)