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A200739
Expansion of (-x^2+5*x-1)/(x^3-x^2+5*x-1).
4
1, 0, 0, 1, 5, 24, 116, 561, 2713, 13120, 63448, 306833, 1483837, 7175800, 34701996, 167818017, 811563889, 3924703424, 18979771248, 91785716705, 443873515701, 2146561633048, 10380720366244, 50200913713873, 242770409836169, 1174031855833216, 5677589783043784
OFFSET
0,5
COMMENTS
Peter Lawrence (see links) has posted a challenge to find a 3x3 integer matrix with "smallish" elements whose powers generate a sequence that is not in the OEIS. This sequence is one of the solutions found.
LINKS
Peter Lawrence et al., sequence challenge and follow-up messages on the SeqFan list, Nov 21 2011
FORMULA
G.f.: (-x^2+5*x-1)/(x^3-x^2+5*x-1).
Term (1,1) in the 3x3 matrix [0,1,0; 0,0,1; 1,-1,5]^n.
MAPLE
a:= n-> (<<0|1|0>, <0|0|1>, <1|-1|5>>^n)[1, 1]:
seq(a(n), n=0..30);
MATHEMATICA
CoefficientList[Series[(-x^2 + 5 x - 1)/(x^3 - x^2 + 5 x - 1), {x, 0, 30}], x] (* or *) LinearRecurrence[{5, -1, 1}, {1, 0, 0}, 30] (* Harvey P. Dale, Nov 26 2017 *)
CROSSREFS
Cf. A200676.
Sequence in context: A057969 A004254 A086347 * A026707 A235115 A110190
KEYWORD
nonn,easy
AUTHOR
Alois P. Heinz, Nov 21 2011
STATUS
approved