OFFSET
1,2
COMMENTS
Row 2 of A181274.
LINKS
R. H. Hardin, Table of n, a(n) for n=1..200
FORMULA
Empirical (for n>=2): 3*4^(n-2) + ((-1)^n-1)*2^(n-4). - Vaclav Kotesovec, Nov 27 2012
Conjectures from Colin Barker, Mar 27 2018: (Start)
G.f.: x^2*(3 - x - 8*x^2) / ((1 - 2*x)*(1 + 2*x)*(1 - 4*x)).
a(n) = 4*a(n-1) + 4*a(n-2) - 16*a(n-3) for n>3.
(End)
EXAMPLE
M and M*Mtranspose (mod 2) for 2 X 3:
..0..1..0......1..1
..0..1..1......1..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Oct 10 2010
STATUS
approved