OFFSET
1,2
LINKS
Colin Barker, Table of n, a(n) for n = 1..1000
Carolina Benedetti, Christopher R. H. Hanusa, Pamela E. Harris, Alejandro H. Morales, Anthony Simpson, Kostant's partition function and magic multiplex juggling sequences, arXiv:2001.03219 [math.CO], 2020. See Table 1 p. 12.
S. Butler and R. Graham, Enumerating (multiplex) juggling sequences, arXiv:0801.2597 [math.CO], 2008.
Index entries for linear recurrences with constant coefficients, signature (10,-27,20).
FORMULA
G.f.: (x-6*x^2+7*x^3)/(1-10*x+27*x^2-20*x^3).
a(n) = 10*a(n-1)-27*a(n-2)+20*a(n-3) for n>3. - Colin Barker, Aug 31 2016
EXAMPLE
a(2)=4 since <3> -> <3> -> <3>; <3> -> <2,1> -> <3>; <3> -> <1,2> -> <3> and <3> -> <0,3> -> <3> are the four possibilities.
MATHEMATICA
LinearRecurrence[{10, -27, 20}, {1, 4, 20}, 30] (* Harvey P. Dale, Sep 17 2020 *)
PROG
(PARI) Vec((x-6*x^2+7*x^3)/(1-10*x+27*x^2-20*x^3) + O(x^30)) \\ Colin Barker, Aug 31 2016
(Magma) R<x>:=PowerSeriesRing(Integers(), 25); Coefficients(R!( (x-6*x^2+7*x^3)/(1-10*x+27*x^2-20*x^3))); // Marius A. Burtea, Jan 13 2020
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Steve Butler, Jan 21 2008
STATUS
approved