OFFSET
1,1
COMMENTS
Row 2 of A212402.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Recurrence: n*a(n) = 2*(4*n-3)*a(n-1) - 8*(2*n-3)*a(n-2). - Vaclav Kotesovec, Oct 19 2012
G.f.: 1/(1-4*x)+1/(2*sqrt(1-4*x)). - Vaclav Kotesovec, Oct 21 2012
a(n) = 4^n + C(2*n-1, n). - Vaclav Kotesovec, Oct 28 2012
EXAMPLE
Some solutions for n=3
..1....0....0....1....0....0....0....1....1....0....1....1....1....0....0....0
..1....0....0....0....1....0....1....0....0....0....1....0....0....1....1....0
..1....0....1....1....0....1....1....0....1....0....0....0....0....0....0....1
..0....1....1....1....0....0....0....0....1....1....0....1....0....0....0....0
..0....0....1....0....1....1....0....1....0....1....1....0....1....1....0....0
..0....1....0....0....1....0....1....0....0....0....0....1....1....0....1....0
..0....1....0....0....0....1....0....1....1....1....0....1....0....0....0....1
MATHEMATICA
Rest[CoefficientList[Series[1/(1-4*x)+1/(2*Sqrt[1-4*x]), {x, 0, 20}], x]] (* Vaclav Kotesovec, Oct 21 2012 *)
Table[4^n + Binomial[2*n-1, n], {n, 1, 20}] (* Vaclav Kotesovec, Oct 28 2012 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, May 14 2012
STATUS
approved