login
a(n) = 5*2^n - 2.
8

%I #33 Oct 27 2023 22:00:44

%S 3,8,18,38,78,158,318,638,1278,2558,5118,10238,20478,40958,81918,

%T 163838,327678,655358,1310718,2621438,5242878,10485758,20971518,

%U 41943038,83886078,167772158,335544318,671088638,1342177278,2684354558,5368709118,10737418238,21474836478

%N a(n) = 5*2^n - 2.

%H Stefano Spezia, <a href="/A051633/b051633.txt">Table of n, a(n) for n = 0..3300</a>

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

%F a(n) = A118654(n, 5).

%F a(n) = A000079(n)*5 - 2 = A020714(n) - 2. - _Omar E. Pol_, Dec 23 2008

%F a(n) = 2*(a(n-1)+1) with a(0)=3. - _Vincenzo Librandi_, Aug 06 2010

%F a(n) = A123208(2*n+1) = A048487(n)+2 = A131051(n+2) = A153894(n)-1. - _Philippe Deléham_, Apr 15 2013

%F G.f.: ( 3-x ) / ( (2*x-1)*(x-1) ). - _R. J. Mathar_, Mar 23 2023

%F E.g.f.: exp(x)*(5*exp(x) - 2). - _Stefano Spezia_, Oct 03 2023

%e a(5) = 5*2^4 - 2 = 80 - 2 = 78.

%t LinearRecurrence[{3, -2},{3, 8},30] (* _Ray Chandler_, Jul 18 2020 *)

%Y Cf. A000079, A020714, A118654.

%Y Cf. A123208, A048487, A131051, A153894.

%K easy,nonn

%O 0,1

%A _Asher Auel_