OFFSET
1,2
COMMENTS
Every 0 is next to 0 4's, every 1 is next to 1 3's, every 2 is next to 2 2's, every 3 is next to 3 1's, every 4 is next to 4 0's
Column 4 of A197217
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 3*a(n-1) +4*a(n-2) +36*a(n-3) +23*a(n-4) -19*a(n-5) -278*a(n-6) -219*a(n-7) -224*a(n-8) +504*a(n-9) +774*a(n-10) -707*a(n-11) -3046*a(n-12) -372*a(n-13) +3206*a(n-14) +2421*a(n-15) -1229*a(n-16) -2776*a(n-17) +652*a(n-18) +3427*a(n-19) +377*a(n-20) -3956*a(n-21) -2455*a(n-22) +2524*a(n-23) +3446*a(n-24) +272*a(n-25) -1845*a(n-26) -1309*a(n-27) -17*a(n-28) +555*a(n-29) +412*a(n-30) +114*a(n-31) -27*a(n-32) -35*a(n-33) -13*a(n-34) -2*a(n-35)
EXAMPLE
Some solutions for n=5
..0..2..2..0....0..0..0..1....2..2..2..0....1..3..1..0....0..0..1..0
..0..2..2..0....0..0..1..3....2..0..2..2....0..1..0..0....0..1..3..1
..0..0..0..0....0..1..0..1....2..0..0..2....0..1..0..0....1..1..3..1
..0..1..0..0....0..3..1..0....2..0..0..2....1..3..2..2....3..1..1..0
..1..3..1..0....0..1..0..0....2..2..2..2....0..1..2..2....1..0..0..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin Oct 11 2011
STATUS
approved