OFFSET
1,1
COMMENTS
Column 3 of A219354.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = (1/24)*n^4 - (1/4)*n^3 + (23/24)*n^2 + (13/4)*n - 8 for n > 3.
Conjectures from Colin Barker, Jul 25 2018: (Start)
G.f.: x*(3 - 12*x + 23*x^2 - 25*x^3 + 17*x^4 - 7*x^5 + 3*x^6 - x^7) / (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 > 8.
(End)
EXAMPLE
Some solutions for n=3:
0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 1 1 1 0 0 1
0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 1 1 1 0 0 1
0 0 0 0 0 1 1 1 1 1 1 1 1 0 0 1 1 1 0 0 1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 18 2012
STATUS
approved