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 1's, every 3 is next to 3 0's, every 4 is next to 4 0's
Column 3 of A197317
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..200
FORMULA
Empirical: a(n) = 2*a(n-2) +3*a(n-3) +17*a(n-4) +a(n-5) +32*a(n-6) -13*a(n-7) -61*a(n-8) -41*a(n-9) -115*a(n-10) -83*a(n-11) -315*a(n-12) -280*a(n-13) -12*a(n-14) +214*a(n-15) -659*a(n-16) +358*a(n-17) +319*a(n-18) +247*a(n-19) -121*a(n-20) -109*a(n-21) -12*a(n-22) +50*a(n-23) +46*a(n-24) +a(n-25) -a(n-26) -3*a(n-27) for n>28
EXAMPLE
Some solutions for n=4
..0..3..0....2..1..1....0..3..0....0..3..0....0..3..0....1..1..0....1..2..1
..3..0..1....1..2..0....1..0..3....3..0..1....1..0..3....0..2..1....1..0..1
..0..2..1....1..0..3....1..2..0....0..2..1....1..2..0....3..0..1....2..1..2
..1..1..2....0..3..0....0..1..1....1..1..0....2..1..1....0..3..0....0..1..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin Oct 13 2011
STATUS
approved