OFFSET
1,2
LINKS
Index entries for linear recurrences with constant coefficients, signature (6,0,1,-6).
FORMULA
a(n) = 6*a(n-1) + a(n-3) - 6*a(n-4).
a(n) = round( (37/215)*6^n ). - Tani Akinari, Jul 15 2014
G.f.: x*(x^2+1) / ((x-1)*(6*x-1)*(x^2+x+1)). - Colin Barker, Jul 15 2014
EXAMPLE
The first six terms have base 6 representations 1, 10, 101, 1011, 10110, 101101. - Michel Marcus, Jul 17 2014
MAPLE
A033124 := proc(n)
coeftayl( (x*(x^2+1) / ((x-1)*(6*x-1)*(x^2+x+1)), x=0, n));
end proc:
seq(A033124(n), n=1..30); # Wesley Ivan Hurt, Jul 17 2014
MATHEMATICA
CoefficientList[Series[(x^2 + 1)/((x - 1)*(6*x - 1)*(x^2 + x + 1)), {x, 0, 30}], x] (* Wesley Ivan Hurt, Jul 17 2014 *)
PROG
(PARI) Vec(x*(x^2+1)/((x-1)*(6*x-1)*(x^2+x+1)) + O(x^100)) \\ Colin Barker, Jul 15 2014
(Magma) [Round((37/215)*6^n) : n in [1..30]]; // Wesley Ivan Hurt, Jul 17 2014
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
EXTENSIONS
More terms from Colin Barker, Jul 15 2014
STATUS
approved