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A190964
a(n) = 3*a(n-1) - 10*a(n-2), with a(0)=0, a(1)=1.
2
0, 1, 3, -1, -33, -89, 63, 1079, 2607, -2969, -34977, -75241, 124047, 1124551, 2133183, -4845961, -35869713, -59149529, 181248543, 1135240919, 1593237327, -6572697209, -35650464897, -41224422601, 232831381167, 1110738369511, 1003901296863, -8095679804521
OFFSET
0,3
FORMULA
G.f.: x/(1-3*x+10*x^2). - Philippe Deléham, Oct 11 2011
From G. C. Greubel, Jan 11 2024: (Start)
a(n) = 10^((n-1)/2)*ChebyshevU(n-1, 3/(2*sqrt(10))).
E.g.f.: (2/sqrt(31))*exp(3*x/2)*sin(sqrt(31)*x/2). (End)
MATHEMATICA
LinearRecurrence[{3, -10}, {0, 1}, 50]
PROG
(PARI) my(x='x+O('x^30)); concat([0], Vec(x/(1-3*x+10*x^2))) \\ G. C. Greubel, Jan 25 2018
(Magma) I:=[0, 1]; [n le 2 select I[n] else 3*Self(n-1) - 10*Self(n-2): n in [1..30]]; // G. C. Greubel, Jan 25 2018
(SageMath)
A190964=BinaryRecurrenceSequence(3, -10, 0, 1)
[A190964(n) for n in range(41)] # G. C. Greubel, Jan 11 2024
CROSSREFS
Cf. A190958 (index to generalized Fibonacci sequences).
Sequence in context: A095844 A113110 A317363 * A109842 A270101 A271288
KEYWORD
sign
AUTHOR
STATUS
approved