OFFSET
1,1
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
Robert Israel, Maple-assisted proof of empirical recurrence
Index entries for linear recurrences with constant coefficients, signature (10, -39, 76, -79, 42, -9).
FORMULA
Empirical: a(n) = 10*a(n-1) - 39*a(n-2) + 76*a(n-3) - 79*a(n-4) + 42*a(n-5) - 9*a(n-6).
Conjectures from Colin Barker, Jan 11 2019: (Start)
G.f.: x*(4 - 27*x + 68*x^2 - 76*x^3 + 42*x^4 - 9*x^5) / ((1 - x)^4*(1 - 3*x)^2).
a(n) = (24 + (31+3^(2+n))*n + 12*n^2 + 2*n^3) / 24.
(End)
Empirical recurrence verified (see link). - Robert Israel, Sep 08 2019
EXAMPLE
Some solutions for n=4:
..0..0..1....0..0..1....0..0..0....0..0..1....0..0..1....0..0..1....0..0..1
..0..1..0....0..1..0....0..1..1....0..0..1....0..1..0....0..0..1....1..1..0
..1..0..0....1..1..0....1..0..1....0..1..1....0..0..1....0..0..1....0..1..1
..1..1..0....1..1..1....0..1..1....0..1..1....0..0..1....1..1..0....1..0..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 12 2016
STATUS
approved