OFFSET
1,4
COMMENTS
Triplicated A000079. Powers of 2 repeated 3 times.
a(n) is the number of ways of partitioning the set of the first n distinct positive Fibonacci numbers into two subsets whose sums differ at most by 1. a(6) = 2: 1,2,5,8/3,13; 1,2,13/3,5,8. - Alois P. Heinz, Jun 16 2019
LINKS
G. C. Greubel, Table of n, a(n) for n = 1..1000
Index entries for linear recurrences with constant coefficients, signature (0,0,2)
FORMULA
G.f. x*(1 + x + x^2)/(1 - 2*x^3). - R. J. Mathar, Nov 28 2011
MATHEMATICA
Flatten[Table[c=2^n; {c, c, c}, {n, 0, 20}]] (* Harvey P. Dale, Jul 20 2012 *)
CoefficientList[Series[x*(1 + x + x^2)/(1 - 2*x^3), {x, 0, 50}], x] (* G. C. Greubel, Apr 30 2017 *)
PROG
(PARI) a(n)=2^((n-1)\3) \\ Charles R Greathouse IV, Oct 03 2016
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Paul Curtz, Nov 26 2010
EXTENSIONS
More terms from Harvey P. Dale, Jul 20 2012
STATUS
approved