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a(n) = 2^n - 243.
0

%I #16 Nov 11 2023 11:00:35

%S -242,-241,-239,-235,-227,-211,-179,-115,13,269,781,1805,3853,7949,

%T 16141,32525,65293,130829,261901,524045,1048333,2096909,4194061,

%U 8388365,16776973,33554189,67108621,134217485,268435213,536870669,1073741581,2147483405,4294967053

%N a(n) = 2^n - 243.

%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.: (485*x - 242)/((x - 1)*(2*x - 1)). (End)

%F From _Elmo R. Oliveira_, Nov 11 2023: (Start)

%F a(n) = 2*a(n-1) + 243 with a(0) = -242.

%F E.g.f.: exp(2*x) - 243*exp(x). (End)

%t Table[2^n - 243, {n, 0, 40}] (* _T. D. Noe_, Dec 04 2012 *)

%Y Cf. A000225, A036563, A185346, A220087, A220088.

%K sign

%O 0,1

%A _Andreas Rieber_, Dec 04 2012