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A220087 a(n) = 2^n - 27. 4

%I #17 Nov 08 2023 06:53:13

%S -26,-25,-23,-19,-11,5,37,101,229,485,997,2021,4069,8165,16357,32741,

%T 65509,131045,262117,524261,1048549,2097125,4194277,8388581,16777189,

%U 33554405,67108837,134217701,268435429,536870885,1073741797,2147483621,4294967269

%N a(n) = 2^n - 27.

%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (3,-2).

%F From _Chai Wah Wu_, Jan 17 2020: (Start)

%F a(n) = 3*a(n-1) - 2*a(n-2) for n > 1.

%F G.f.: (53*x - 26)/((x - 1)*(2*x - 1)). (End)

%F From _Elmo R. Oliveira_, Nov 08 2023: (Start)

%F a(n) = 2*a(n-1) + 27 with a(0) = -26.

%F E.g.f.: exp(2*x) - 27*exp(x). (End)

%t Table[2^n - 27, {n, 0, 40}] (* _T. D. Noe_, Dec 04 2012 *)

%t LinearRecurrence[{3,-2},{-26,-25},40] (* _Harvey P. Dale_, May 17 2018 *)

%Y Cf. A000225, A036563, A185346.

%K sign

%O 0,1

%A _Andreas Rieber_, Dec 04 2012

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Last modified April 25 01:35 EDT 2024. Contains 371964 sequences. (Running on oeis4.)