OFFSET
1,1
COMMENTS
Every 0 is next to 0 4's, every 1 is next to 1 3's, every 2 is next to 2 0's, every 3 is next to 3 1's, every 4 is next to 4 1's
Column 3 of A198155
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..200
FORMULA
Empirical: a(n) = 2*a(n-1) +3*a(n-2) +38*a(n-3) +40*a(n-4) +21*a(n-5) -127*a(n-6) -313*a(n-7) -143*a(n-8) +681*a(n-9) +1988*a(n-10) +1587*a(n-11) -1232*a(n-12) -4569*a(n-13) -5344*a(n-14) -992*a(n-15) +3626*a(n-16) +4576*a(n-17) +2900*a(n-18) +162*a(n-19) -844*a(n-20) -954*a(n-21) -250*a(n-22) +190*a(n-23) +34*a(n-24) -a(n-25)
EXAMPLE
Some solutions for n=4
..2..0..0....0..0..0....2..0..2....0..0..0....0..1..0....0..1..0....0..1..0
..0..0..0....0..0..0....0..0..0....0..1..0....1..3..1....1..3..0....0..3..1
..1..3..1....2..2..2....0..2..2....1..3..2....1..3..1....0..1..2....0..1..0
..0..1..0....0..0..0....0..2..0....0..1..0....0..1..0....2..0..0....0..0..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin Oct 21 2011
STATUS
approved