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A033124
Base-6 digits are, in order, the first n terms of the periodic sequence with initial period 1,0,1.
1
1, 6, 37, 223, 1338, 8029, 48175, 289050, 1734301, 10405807, 62434842, 374609053, 2247654319, 13485925914, 80915555485, 485493332911, 2912959997466, 17477759984797, 104866559908783, 629199359452698, 3775196156716189, 22651176940297135, 135907061641782810
OFFSET
1,2
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
Cf. A033128 (similar in base 10).
Sequence in context: A081152 A244618 A033116 * A288786 A180032 A022035
KEYWORD
nonn,base,easy
EXTENSIONS
More terms from Colin Barker, Jul 15 2014
STATUS
approved