OFFSET
1,2
COMMENTS
Column 6 of A221573
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 7*a(n-1) -4*a(n-2) +6*a(n-3) +26*a(n-4) +10*a(n-5) +16*a(n-6) +12*a(n-8).
Empirical: -x^2*(37-62*x+138*x^2-26*x^3+100*x^4-36*x^5+48*x^6) / ( -1+7*x-4*x^2+6*x^3+26*x^4+10*x^5+16*x^6+12*x^8 ). - R. J. Mathar, Jun 06 2013
EXAMPLE
Some solutions for n=6
..4....2....5....0....4....4....2....3....1....3....6....0....5....4....0....2
..6....5....1....2....4....6....5....5....4....1....6....2....0....6....6....2
..2....5....6....5....5....2....2....5....1....0....2....3....0....5....1....5
..4....4....6....2....3....3....5....6....1....0....6....1....6....1....5....1
..6....2....0....5....4....1....1....6....1....0....0....3....4....3....5....4
..6....4....2....5....1....5....6....4....4....4....4....0....2....3....3....2
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin Jan 20 2013
STATUS
approved