OFFSET
1,1
COMMENTS
Row 2 of A214112
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 4*a(n-1) +22*a(n-2) -4*a(n-3) -21*a(n-4).
Empirical: G.f. -x*(7*x+4)*(3*x-1) / ( (x-1)*(3*x+1)*(7*x-1)*(1+x) ), a(n) = 11/24 +3*(-1)^(n+1)/8 +7^(n+1)/24 +(-3)^(n+1)/8. - R. J. Mathar, Jul 04 2012
EXAMPLE
Some solutions for n=4
..0..1..0..2..3....0..1..2..0..1....0..1..2..3..1....0..1..2..0..3
..1..2..1..3..0....1..2..3..1..0....3..2..0..1..2....3..0..1..2..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin Jul 04 2012
STATUS
approved