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A190870 a(n) = 11*a(n-1) - 22*a(n-2), a(0)=0, a(1)=1. 1
0, 1, 11, 99, 847, 7139, 59895, 501787, 4201967, 35182323, 294562279, 2466173963, 20647543455, 172867150819, 1447292702999, 12117142414971, 101448127098703, 849352264956371, 7111016118348615, 59535427472794603, 498447347597071103, 4173141419166300867 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

G. C. Greubel, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (11, -22).

FORMULA

a(n) = ((11+sqrt(33))^n-(11-sqrt(33))^n)/(2^n*sqrt(33)).

E.g.f.: (2/sqrt(33))*exp(11*x/2)*sinh(sqrt(33)*x/2). - G. C. Greubel, Dec 18 2015

G.f.: x/(1-11*x+22*x^2). - G. C. Greubel, Dec 18 2015

MATHEMATICA

LinearRecurrence[{11, -22}, {0, 1}, 50] (* T. D. Noe, May 23 2011 *)

PROG

(PARI) concat(0, Vec(x/(1-11*x+22*x^2) + O(x^100))) \\ Altug Alkan, Dec 18 2015

CROSSREFS

Cf. A190871, A190872, A190873

Sequence in context: A130886 A239486 A015671 * A037510 A037693 A098611

Adjacent sequences:  A190867 A190868 A190869 * A190871 A190872 A190873

KEYWORD

nonn

AUTHOR

Rolf Pleisch, May 22 2011

EXTENSIONS

Extended by T. D. Noe, May 23 2011

STATUS

approved

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Last modified August 6 15:50 EDT 2020. Contains 336255 sequences. (Running on oeis4.)