A168616 a(n) = 2^n - 5.
-4, -3, -1, 3, 11, 27, 59, 123, 251, 507, 1019, 2043, 4091, 8187, 16379, 32763, 65531, 131067, 262139, 524283, 1048571, 2097147, 4194299, 8388603, 16777211, 33554427, 67108859, 134217723, 268435451, 536870907, 1073741819, 2147483643
Offset: 0
Links
- Vincenzo Librandi, Table of n, a(n) for n = 0..1000
- Index entries for linear recurrences with constant coefficients, signature(3,-2).
Programs
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Magma
[2^n-5: n in [0..40]]; // Vincenzo Librandi, Sep 19 2013
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Mathematica
Table[2^n-5,{n,0,5!}] (* Vladimir Joseph Stephan Orlovsky, Nov 22 2010 *) CoefficientList[Series[(9 x - 4)/((x - 1) (2 x - 1)), {x, 0, 60}], x] (* Vincenzo Librandi, Sep 19 2013 *) LinearRecurrence[{3,-2},{-4,-3},40] (* Harvey P. Dale, Oct 15 2014 *) -
PARI
a(n)=2^n-5 \\ Charles R Greathouse IV, Oct 07 2015
Formula
a(n) = 2*a(n-1) + 5.
G.f. (9*x - 4)/((x-1)*(2*x-1)). - R. J. Mathar, Feb 22 2012
a(n) = 3*a(n-1) - 2*a(n-2). - Vincenzo Librandi, Sep 19 2013
E.g.f.: exp(2*x) - 5*exp(x). - G. C. Greubel, Jul 27 2016
Extensions
Formula and examples edited to use correct offset by Jon E. Schoenfield, Jun 19 2010