OFFSET
0,2
COMMENTS
LINKS
Bruno Berselli, Table of n, a(n) for n = 0..1000
Bruno Berselli, Illustration of initial terms: An origin of A195241.
Index entries for linear recurrences with constant coefficients, signature (3,-3,1).
FORMULA
G.f.: (1-x+19*x^3-3*x^4)/(1-x)^3.
a(n) = 8*n^2-20*n+11 for n>1; a(0)=1, a(1)=2.
MATHEMATICA
CoefficientList[Series[(1 - x + 19 x^3 - 3 x^4)/(1 - x)^3, {x, 0, 50}], x] (* Vincenzo Librandi, Mar 26 2013 *)
LinearRecurrence[{3, -3, 1}, {1, 2, 3, 23, 59}, 50] (* Harvey P. Dale, Dec 04 2022 *)
PROG
(PARI) Vec((1-x+19*x^3-3*x^4)/(1-x)^3+O(x^44))
(Magma) m:=44; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!((1-x+19*x^3-3*x^4)/(1-x)^3));
(Maxima) makelist(coeff(taylor((1-x+19*x^3-3*x^4)/(1-x)^3, x, 0, n), x, n), n, 0, 43);
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Bruno Berselli, Sep 13 2011 - based on remarks and sequences by Omar E. Pol.
STATUS
approved