%I #14 Aug 28 2023 14:29:32
%S 6,19,58,175,526,1579,4738,14215,42646,127939,383818,1151455,3454366,
%T 10363099,31089298,93267895,279803686,839411059,2518233178,7554699535,
%U 22664098606,67992295819,203976887458,611930662375,1835791987126,5507375961379,16522127884138
%N a(n) = (13*3^n-1)/2.
%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (4,-3).
%F a(n) = 3*a(n-1) + 1, a(0)=6.
%F a(n) = 4*a(n-1) - 3*a(n-2), a(0)=6, a(1)=19.
%F a(n) = 2*A237930(n) - A003462(n).
%F a(n) = A052909(n+1) + A000244(n).
%F a(n) = A237930(n) + A000244(n+1).
%F a(n) = 13*A003462(n) + 6.
%F G.f.: (6-5*x)/((1-x)*(1-3*x)).
%F E.g.f.: exp(x)*(13*exp(2*x) - 1)/2. - _Stefano Spezia_, Aug 28 2023
%e Ternary....................Decimal
%e 20...............................6
%e 201.............................19
%e 2011............................58
%e 20111..........................175
%e 201111.........................526
%e 2011111.......................1579
%e 20111111......................4738
%e 201111111....................14215, etc.
%Y Cf. A000244, A003462, A052909, A060816, A237930.
%K nonn,easy
%O 0,1
%A _Philippe Deléham_, Feb 17 2014