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A168520
a(n) = 98*a(n-1) - a(n-2); a(1) = 0, a(2) = 10.
5
0, 10, 980, 96030, 9409960, 922080050, 90354434940, 8853812544070, 867583274883920, 85014307126080090, 8330534515080964900, 816307368170808480110, 79989791546224150085880, 7838183264161795899936130, 768061970096309774043654860, 75262234886174196060378240150
OFFSET
1,2
FORMULA
From Colin Barker, Oct 08 2015: (Start)
a(n) = 98*a(n-1) - a(n-2) for n>2.
O.g.f.: 10*x^2 / (x^2-98*x+1). (End)
E.g.f.: exp(49*x)*( (49/(2*sqrt(6)))*sinh(20*sqrt(6)*x) - 10*cosh(20*sqrt(6)*x) ) + 10. - G. C. Greubel, Jul 24 2016
MATHEMATICA
LinearRecurrence[{98, -1}, {0, 10}, 30] (* Harvey P. Dale, Sep 19 2011 *)
CoefficientList[Series[10 x/(x^2 - 98 x + 1), {x, 0, 33}], x] (* Vincenzo Librandi, Oct 13 2015 *)
PROG
(PARI) concat(0, Vec(10*x^2/(x^2-98*x+1) + O(x^30))) \\ Colin Barker, Oct 08 2015
(Magma) I:=[0, 10]; [n le 2 select I[n] else 98*Self(n-1)-Self(n-2): n in [1..40]]; // Vincenzo Librandi, Oct 13 2015
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Mark Dols, Nov 28 2009
EXTENSIONS
a(1)=1 changed to a(1)=10, and data changed accordingly, so sequence is a bisection of A004189- Mark Dols, Feb 01 2010
Changed name to match data and offset, Joerg Arndt, Oct 13 2015
STATUS
approved