OFFSET
1,1
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = n^4 + 4*n^3 + 6*n^2 + 3*n + 3 for n>1.
Conjectures from Colin Barker, Nov 13 2018: (Start)
G.f.: x*(16 + x + 10*x^2 - 2*x^3 - 2*x^4 + x^5) / (1 - x)^5.
a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5) for n>6.
(End)
EXAMPLE
Some solutions for n=6:
..1....2....1....3....1....5....3....5....0....0....5....0....5....3....2....4
..2....3....5....7....4....6....4....3....3....2....6....5....4....4....4....6
..8....4....2....5....2....8....7....2....6....5....4....7....6....7....3....2
..3....6....6....9....9....6....7....4....8....7....5....6....7....9....4....9
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 19 2014
STATUS
approved