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A064333
Generalized Catalan numbers C(-11; n).
5
1, 1, -10, 221, -6082, 187386, -6184848, 213843477, -7645509706, 280351640702, -10485617230780, 398467433529298, -15341431926699284, 597149747213056324, -23459916801814723548, 929028306450848244741, -37045540042729366580442
OFFSET
0,3
COMMENTS
See triangle A064334 with columns m built from C(-m; n), m >= 0, also for Derrida et al. references.
LINKS
FORMULA
a(n) = Sum_{m-0..n-1} (n-m)*binomial(n-1+m, m)*(-11)^m/n.
a(n) = (1/12)^n*(1 + 11*Sum_{k=0..n-1} C(k)*(-11*12)^k ), n >= 1, a(0) := 1; with C(n)=A000108(n) (Catalan).
G.f.: (1+11*x*c(-11*x)/12)/(1-x/12) = 1/(1-x*c(-11*x)) with c(x) g.f. of Catalan numbers A000108.
MATHEMATICA
CoefficientList[Series[(23 +Sqrt[1+44*x])/(2*(12-x)), {x, 0, 30}], x] (* G. C. Greubel, May 03 2019 *)
PROG
(PARI) my(x='x+O('x^30)); Vec((23 +sqrt(1+44*x))/(2*(12-x))) \\ G. C. Greubel, May 03 2019
(Magma) R<x>:=PowerSeriesRing(Rationals(), 30); Coefficients(R!( (23 +Sqrt(1+44*x))/(2*(12-x)) )); // G. C. Greubel, May 03 2019
(Sage) ((23 +sqrt(1+44*x))/(2*(12-x))).series(x, 30).coefficients(x, sparse=False) # G. C. Greubel, May 03 2019
CROSSREFS
Sequence in context: A166181 A199748 A210137 * A223817 A317171 A229256
KEYWORD
sign,easy
AUTHOR
Wolfdieter Lang, Sep 21 2001
STATUS
approved