OFFSET
1,1
COMMENTS
Every 0 is next to 0 2's, every 1 is next to 1 0's, every 2 is next to 2 3's, every 3 is next to 3 1's, every 4 is next to 4 4's.
Column 3 of A196287.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..200
FORMULA
Empirical: a(n) = 3*a(n-1) -a(n-3) -5*a(n-4) +6*a(n-5) +2*a(n-6) -14*a(n-7) -63*a(n-8) -7*a(n-9) +88*a(n-10) +28*a(n-11) +122*a(n-12) -20*a(n-13) -48*a(n-14).
EXAMPLE
Some solutions for n=4
..1..1..0....0..0..1....0..0..1....0..0..0....1..0..0....1..1..1....1..0..0
..0..1..1....1..1..1....1..3..1....1..3..1....1..0..0....0..0..0....1..1..1
..0..1..1....1..3..0....1..1..0....1..1..3....1..0..0....0..0..0....0..1..1
..1..1..0....0..1..1....0..1..1....0..0..1....1..0..0....0..0..0....1..1..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Sep 30 2011
STATUS
approved