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!)
A197470 Number of nX3 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 0,1,0,0,0 for x=0,1,2,3,4 1
3, 6, 26, 46, 181, 374, 1300, 2886, 9446, 22060, 69096, 167466, 507600, 1265434, 3741192, 9529514, 27644128, 71580304, 204668940, 536641128, 1517618972, 4017418484, 11266355518, 30042504088, 83713614532, 224474050480 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Every 0 is next to 0 0's, every 1 is next to 1 1's, every 2 is next to 2 0's, every 3 is next to 3 0's, every 4 is next to 4 0's
Column 3 of A197475
LINKS
FORMULA
Empirical: a(n) = 6*a(n-2) +3*a(n-3) +4*a(n-4) -2*a(n-5) +2*a(n-6) -7*a(n-7) -19*a(n-8) -23*a(n-9) -19*a(n-10) -19*a(n-11) -4*a(n-12) -4*a(n-13) for n>16
EXAMPLE
Some solutions containing all values 0 to 4 for n=4
..0..1..1....2..0..2....1..2..0....2..0..2....2..0..2....2..0..2....1..1..0
..3..0..2....0..4..0....1..0..3....0..4..0....0..4..0....0..4..0....2..0..3
..0..4..0....1..0..3....0..4..0....2..0..3....3..0..2....3..0..1....0..4..0
..2..0..2....1..2..0....2..0..2....1..1..0....0..1..1....0..2..1....2..0..2
CROSSREFS
Sequence in context: A212650 A297572 A137089 * A148664 A148665 A148666
KEYWORD
nonn
AUTHOR
R. H. Hardin Oct 15 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 | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 28 18:04 EDT 2024. Contains 371254 sequences. (Running on oeis4.)