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!)
A221828 T(n,k)=Number of nXk arrays of occupancy after each element moves to some horizontal, vertical or antidiagonal neighbor, without 2-loops or left turns 8
0, 0, 0, 0, 3, 0, 0, 16, 14, 0, 0, 73, 202, 64, 0, 0, 333, 2879, 2930, 292, 0, 0, 1519, 40983, 115417, 41618, 1332, 0, 0, 6929, 583419, 4715043, 4755445, 592601, 6076, 0, 0, 31607, 8304016, 192788993, 570066685, 194407111, 8434490, 27716, 0, 0, 144177 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,5

COMMENTS

Table starts

.0......0..........0............0.............0..............0.............0

.0......3.........16...........73...........333...........1519..........6929

.0.....14........202.........2879.........40983.........583419.......8304016

.0.....64.......2930.......115417.......4715043......192788993....7888216533

.0....292......41618......4755445.....570066685....68573607669.8233561918895

.0...1332.....592601....194407111...68489860450.24121109763712

.0...6076....8434490...7954432829.8224749361083

.0..27716..120053263.325446165881

.0.126428.1708776751

.0.576708

.0

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..71

FORMULA

Empirical for col 2: a(n) = 5*a(n-1) -2*a(n-2) for n>3

Empirical for row 2: a(k)=5*a(k-1)-2*a(k-2) for k>4

EXAMPLE

Some solutions for n=3 k=4

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

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

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

CROSSREFS

Column 2 is A060801(n-1)

Sequence in context: A278208 A105786 A291802 * A278188 A101192 A228622

Adjacent sequences:  A221825 A221826 A221827 * A221829 A221830 A221831

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin Jan 26 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 | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified October 22 22:22 EDT 2020. Contains 337962 sequences. (Running on oeis4.)